Imported WebKit commit 2ea9d364d0f6efa8fa64acf19f451504c59be0e4 (http://svn.webkit.org/repository/webkit/trunk@104285)

1 files changed, 1549 insertions, 0 deletions

diff --git a/Source/WebCore/rendering/InlineFlowBox.cpp b/Source/WebCore/rendering/InlineFlowBox.cpp
new file mode 100644
index 000000000..fb93b62c2
--- /dev/null
+++ b/Source/WebCore/rendering/InlineFlowBox.cpp
@@ -0,0 +1,1549 @@
+/*
+ * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public License
+ * along with this library; see the file COPYING.LIB.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA 02110-1301, USA.
+ */
+
+#include "config.h"
+#include "InlineFlowBox.h"
+
+#include "CachedImage.h"
+#include "CSSPropertyNames.h"
+#include "Document.h"
+#include "EllipsisBox.h"
+#include "GraphicsContext.h"
+#include "InlineTextBox.h"
+#include "HitTestResult.h"
+#include "RootInlineBox.h"
+#include "RenderBlock.h"
+#include "RenderInline.h"
+#include "RenderLayer.h"
+#include "RenderListMarker.h"
+#include "RenderRubyBase.h"
+#include "RenderRubyRun.h"
+#include "RenderRubyText.h"
+#include "RenderTableCell.h"
+#include "RootInlineBox.h"
+#include "Text.h"
+
+#include <math.h>
+
+using namespace std;
+
+namespace WebCore {
+
+#ifndef NDEBUG
+
+InlineFlowBox::~InlineFlowBox()
+{
+    if (!m_hasBadChildList)
+        for (InlineBox* child = firstChild(); child; child = child->nextOnLine())
+            child->setHasBadParent();
+}
+
+#endif
+
+int InlineFlowBox::getFlowSpacingLogicalWidth()
+{
+    int totWidth = marginBorderPaddingLogicalLeft() + marginBorderPaddingLogicalRight();
+    for (InlineBox* curr = firstChild(); curr; curr = curr->nextOnLine()) {
+        if (curr->isInlineFlowBox())
+            totWidth += toInlineFlowBox(curr)->getFlowSpacingLogicalWidth();
+    }
+    return totWidth;
+}
+
+IntRect InlineFlowBox::roundedFrameRect() const
+{
+    // Begin by snapping the x and y coordinates to the nearest pixel.
+    int snappedX = lroundf(x());
+    int snappedY = lroundf(y());
+    
+    int snappedMaxX = lroundf(x() + width());
+    int snappedMaxY = lroundf(y() + height());
+    
+    return IntRect(snappedX, snappedY, snappedMaxX - snappedX, snappedMaxY - snappedY);
+}
+
+static void setHasTextDescendantsOnAncestors(InlineFlowBox* box)
+{
+    while (box && !box->hasTextDescendants()) {
+        box->setHasTextDescendants();
+        box = box->parent();
+    }
+}
+
+void InlineFlowBox::addToLine(InlineBox* child) 
+{
+    ASSERT(!child->parent());
+    ASSERT(!child->nextOnLine());
+    ASSERT(!child->prevOnLine());
+    checkConsistency();
+
+    child->setParent(this);
+    if (!m_firstChild) {
+        m_firstChild = child;
+        m_lastChild = child;
+    } else {
+        m_lastChild->setNextOnLine(child);
+        child->setPrevOnLine(m_lastChild);
+        m_lastChild = child;
+    }
+    child->setFirstLineStyleBit(m_firstLine);
+    child->setIsHorizontal(isHorizontal());
+    if (child->isText()) {
+        if (child->renderer()->parent() == renderer())
+            m_hasTextChildren = true;
+        setHasTextDescendantsOnAncestors(this);
+    } else if (child->isInlineFlowBox()) {
+        if (toInlineFlowBox(child)->hasTextDescendants())
+            setHasTextDescendantsOnAncestors(this);
+    }
+
+    if (descendantsHaveSameLineHeightAndBaseline() && !child->renderer()->isPositioned()) {
+        RenderStyle* parentStyle = renderer()->style(m_firstLine);
+        RenderStyle* childStyle = child->renderer()->style(m_firstLine);
+        bool shouldClearDescendantsHaveSameLineHeightAndBaseline = false;
+        if (child->renderer()->isReplaced())
+            shouldClearDescendantsHaveSameLineHeightAndBaseline = true;
+        else if (child->isText()) {
+            if (child->renderer()->isBR() || child->renderer()->parent() != renderer()) {
+                if (!parentStyle->font().fontMetrics().hasIdenticalAscentDescentAndLineGap(childStyle->font().fontMetrics())
+                    || parentStyle->lineHeight() != childStyle->lineHeight()
+                    || (parentStyle->verticalAlign() != BASELINE && !isRootInlineBox()) || childStyle->verticalAlign() != BASELINE)
+                    shouldClearDescendantsHaveSameLineHeightAndBaseline = true;
+            }
+            if (childStyle->hasTextCombine() || childStyle->textEmphasisMark() != TextEmphasisMarkNone)
+                shouldClearDescendantsHaveSameLineHeightAndBaseline = true;
+        } else {
+            if (child->renderer()->isBR()) {
+                // FIXME: This is dumb. We only turn off because current layout test results expect the <br> to be 0-height on the baseline.
+                // Other than making a zillion tests have to regenerate results, there's no reason to ditch the optimization here.
+                shouldClearDescendantsHaveSameLineHeightAndBaseline = true;
+            } else {
+                ASSERT(isInlineFlowBox());
+                InlineFlowBox* childFlowBox = toInlineFlowBox(child);
+                // Check the child's bit, and then also check for differences in font, line-height, vertical-align
+                if (!childFlowBox->descendantsHaveSameLineHeightAndBaseline()
+                    || !parentStyle->font().fontMetrics().hasIdenticalAscentDescentAndLineGap(childStyle->font().fontMetrics())
+                    || parentStyle->lineHeight() != childStyle->lineHeight()
+                    || (parentStyle->verticalAlign() != BASELINE && !isRootInlineBox()) || childStyle->verticalAlign() != BASELINE
+                    || childStyle->hasBorder() || childStyle->hasPadding() || childStyle->hasTextCombine())
+                    shouldClearDescendantsHaveSameLineHeightAndBaseline = true;
+            }
+        }
+
+        if (shouldClearDescendantsHaveSameLineHeightAndBaseline)
+            clearDescendantsHaveSameLineHeightAndBaseline();
+    }
+
+    if (!child->renderer()->isPositioned()) {
+        if (child->isText()) {
+            RenderStyle* childStyle = child->renderer()->style(m_firstLine);
+            if (childStyle->letterSpacing() < 0 || childStyle->textShadow() || childStyle->textEmphasisMark() != TextEmphasisMarkNone || childStyle->textStrokeWidth())
+                child->clearKnownToHaveNoOverflow();
+        } else if (child->renderer()->isReplaced()) {
+            RenderBox* box = toRenderBox(child->renderer());
+            if (box->hasRenderOverflow() || box->hasSelfPaintingLayer())
+                child->clearKnownToHaveNoOverflow();
+        } else if (!child->renderer()->isBR() && (child->renderer()->style(m_firstLine)->boxShadow() || child->boxModelObject()->hasSelfPaintingLayer()
+                   || (child->renderer()->isListMarker() && !toRenderListMarker(child->renderer())->isInside())
+                   || child->renderer()->style(m_firstLine)->hasBorderImageOutsets()))
+            child->clearKnownToHaveNoOverflow();
+        
+        if (knownToHaveNoOverflow() && child->isInlineFlowBox() && !toInlineFlowBox(child)->knownToHaveNoOverflow())
+            clearKnownToHaveNoOverflow();
+    }
+
+    checkConsistency();
+}
+
+void InlineFlowBox::removeChild(InlineBox* child)
+{
+    checkConsistency();
+
+    if (!m_dirty)
+        dirtyLineBoxes();
+
+    root()->childRemoved(child);
+
+    if (child == m_firstChild)
+        m_firstChild = child->nextOnLine();
+    if (child == m_lastChild)
+        m_lastChild = child->prevOnLine();
+    if (child->nextOnLine())
+        child->nextOnLine()->setPrevOnLine(child->prevOnLine());
+    if (child->prevOnLine())
+        child->prevOnLine()->setNextOnLine(child->nextOnLine());
+    
+    child->setParent(0);
+
+    checkConsistency();
+}
+
+void InlineFlowBox::deleteLine(RenderArena* arena)
+{
+    InlineBox* child = firstChild();
+    InlineBox* next = 0;
+    while (child) {
+        ASSERT(this == child->parent());
+        next = child->nextOnLine();
+#ifndef NDEBUG
+        child->setParent(0);
+#endif
+        child->deleteLine(arena);
+        child = next;
+    }
+#ifndef NDEBUG
+    m_firstChild = 0;
+    m_lastChild = 0;
+#endif
+
+    removeLineBoxFromRenderObject();
+    destroy(arena);
+}
+
+void InlineFlowBox::removeLineBoxFromRenderObject()
+{
+    toRenderInline(renderer())->lineBoxes()->removeLineBox(this);
+}
+
+void InlineFlowBox::extractLine()
+{
+    if (!m_extracted)
+        extractLineBoxFromRenderObject();
+    for (InlineBox* child = firstChild(); child; child = child->nextOnLine())
+        child->extractLine();
+}
+
+void InlineFlowBox::extractLineBoxFromRenderObject()
+{
+    toRenderInline(renderer())->lineBoxes()->extractLineBox(this);
+}
+
+void InlineFlowBox::attachLine()
+{
+    if (m_extracted)
+        attachLineBoxToRenderObject();
+    for (InlineBox* child = firstChild(); child; child = child->nextOnLine())
+        child->attachLine();
+}
+
+void InlineFlowBox::attachLineBoxToRenderObject()
+{
+    toRenderInline(renderer())->lineBoxes()->attachLineBox(this);
+}
+
+void InlineFlowBox::adjustPosition(float dx, float dy)
+{
+    InlineBox::adjustPosition(dx, dy);
+    for (InlineBox* child = firstChild(); child; child = child->nextOnLine())
+        child->adjustPosition(dx, dy);
+    if (m_overflow)
+        m_overflow->move(dx, dy); // FIXME: Rounding error here since overflow was pixel snapped, but nobody other than list markers passes non-integral values here.
+}
+
+RenderLineBoxList* InlineFlowBox::rendererLineBoxes() const
+{
+    return toRenderInline(renderer())->lineBoxes();
+}
+
+static inline bool isLastChildForRenderer(RenderObject* ancestor, RenderObject* child)
+{
+    if (!child)
+        return false;
+    
+    if (child == ancestor)
+        return true;
+
+    RenderObject* curr = child;
+    RenderObject* parent = curr->parent();
+    while (parent && (!parent->isRenderBlock() || parent->isInline())) {
+        if (parent->lastChild() != curr)
+            return false;
+        if (parent == ancestor)
+            return true;
+            
+        curr = parent;
+        parent = curr->parent();
+    }
+
+    return true;
+}
+
+static bool isAnsectorAndWithinBlock(RenderObject* ancestor, RenderObject* child)
+{
+    RenderObject* object = child;
+    while (object && (!object->isRenderBlock() || object->isInline())) {
+        if (object == ancestor)
+            return true;
+        object = object->parent();
+    }
+    return false;
+}
+
+void InlineFlowBox::determineSpacingForFlowBoxes(bool lastLine, bool isLogicallyLastRunWrapped, RenderObject* logicallyLastRunRenderer)
+{
+    // All boxes start off open.  They will not apply any margins/border/padding on
+    // any side.
+    bool includeLeftEdge = false;
+    bool includeRightEdge = false;
+
+    // The root inline box never has borders/margins/padding.
+    if (parent()) {
+        bool ltr = renderer()->style()->isLeftToRightDirection();
+
+        // Check to see if all initial lines are unconstructed.  If so, then
+        // we know the inline began on this line (unless we are a continuation).
+        RenderLineBoxList* lineBoxList = rendererLineBoxes();
+        if (!lineBoxList->firstLineBox()->isConstructed() && !renderer()->isInlineElementContinuation()) {
+            if (ltr && lineBoxList->firstLineBox() == this)
+                includeLeftEdge = true;
+            else if (!ltr && lineBoxList->lastLineBox() == this)
+                includeRightEdge = true;
+        }
+
+        if (!lineBoxList->lastLineBox()->isConstructed()) {
+            RenderInline* inlineFlow = toRenderInline(renderer());
+            bool isLastObjectOnLine = !isAnsectorAndWithinBlock(renderer(), logicallyLastRunRenderer) || (isLastChildForRenderer(renderer(), logicallyLastRunRenderer) && !isLogicallyLastRunWrapped);
+
+            // We include the border under these conditions:
+            // (1) The next line was not created, or it is constructed. We check the previous line for rtl.
+            // (2) The logicallyLastRun is not a descendant of this renderer.
+            // (3) The logicallyLastRun is a descendant of this renderer, but it is the last child of this renderer and it does not wrap to the next line.
+            
+            if (ltr) {
+                if (!nextLineBox()
+                    && ((lastLine || isLastObjectOnLine) && !inlineFlow->continuation()))
+                    includeRightEdge = true;
+            } else {
+                if ((!prevLineBox() || prevLineBox()->isConstructed())
+                    && ((lastLine || isLastObjectOnLine) && !inlineFlow->continuation()))
+                    includeLeftEdge = true;
+            }
+        }
+    }
+
+    setEdges(includeLeftEdge, includeRightEdge);
+
+    // Recur into our children.
+    for (InlineBox* currChild = firstChild(); currChild; currChild = currChild->nextOnLine()) {
+        if (currChild->isInlineFlowBox()) {
+            InlineFlowBox* currFlow = toInlineFlowBox(currChild);
+            currFlow->determineSpacingForFlowBoxes(lastLine, isLogicallyLastRunWrapped, logicallyLastRunRenderer);
+        }
+    }
+}
+
+float InlineFlowBox::placeBoxesInInlineDirection(float logicalLeft, bool& needsWordSpacing, GlyphOverflowAndFallbackFontsMap& textBoxDataMap)
+{
+    // Set our x position.
+    setLogicalLeft(logicalLeft);
+  
+    float startLogicalLeft = logicalLeft;
+    logicalLeft += borderLogicalLeft() + paddingLogicalLeft();
+
+    float minLogicalLeft = startLogicalLeft;
+    float maxLogicalRight = logicalLeft;
+
+    for (InlineBox* curr = firstChild(); curr; curr = curr->nextOnLine()) {
+        if (curr->renderer()->isText()) {
+            InlineTextBox* text = toInlineTextBox(curr);
+            RenderText* rt = toRenderText(text->renderer());
+            if (rt->textLength()) {
+                if (needsWordSpacing && isSpaceOrNewline(rt->characters()[text->start()]))
+                    logicalLeft += rt->style(m_firstLine)->font().wordSpacing();
+                needsWordSpacing = !isSpaceOrNewline(rt->characters()[text->end()]);
+            }
+            text->setLogicalLeft(logicalLeft);
+            if (knownToHaveNoOverflow())
+                minLogicalLeft = min(logicalLeft, minLogicalLeft);
+            logicalLeft += text->logicalWidth();
+            if (knownToHaveNoOverflow())
+                maxLogicalRight = max(logicalLeft, maxLogicalRight);
+        } else {
+            if (curr->renderer()->isPositioned()) {
+                if (curr->renderer()->parent()->style()->isLeftToRightDirection())
+                    curr->setLogicalLeft(logicalLeft);
+                else
+                    // Our offset that we cache needs to be from the edge of the right border box and
+                    // not the left border box.  We have to subtract |x| from the width of the block
+                    // (which can be obtained from the root line box).
+                    curr->setLogicalLeft(root()->block()->logicalWidth() - logicalLeft);
+                continue; // The positioned object has no effect on the width.
+            }
+            if (curr->renderer()->isRenderInline()) {
+                InlineFlowBox* flow = toInlineFlowBox(curr);
+                logicalLeft += flow->marginLogicalLeft();
+                if (knownToHaveNoOverflow())
+                    minLogicalLeft = min(logicalLeft, minLogicalLeft);
+                logicalLeft = flow->placeBoxesInInlineDirection(logicalLeft, needsWordSpacing, textBoxDataMap);
+                if (knownToHaveNoOverflow())
+                    maxLogicalRight = max(logicalLeft, maxLogicalRight);
+                logicalLeft += flow->marginLogicalRight();
+            } else if (!curr->renderer()->isListMarker() || toRenderListMarker(curr->renderer())->isInside()) {
+                // The box can have a different writing-mode than the overall line, so this is a bit complicated.
+                // Just get all the physical margin and overflow values by hand based off |isVertical|.
+                int logicalLeftMargin = isHorizontal() ? curr->boxModelObject()->marginLeft() : curr->boxModelObject()->marginTop();
+                int logicalRightMargin = isHorizontal() ? curr->boxModelObject()->marginRight() : curr->boxModelObject()->marginBottom();
+                
+                logicalLeft += logicalLeftMargin;
+                curr->setLogicalLeft(logicalLeft);
+                if (knownToHaveNoOverflow())
+                    minLogicalLeft = min(logicalLeft, minLogicalLeft);
+                logicalLeft += curr->logicalWidth();
+                if (knownToHaveNoOverflow())
+                    maxLogicalRight = max(logicalLeft, maxLogicalRight);
+                logicalLeft += logicalRightMargin;
+            }
+        }
+    }
+
+    logicalLeft += borderLogicalRight() + paddingLogicalRight();
+    setLogicalWidth(logicalLeft - startLogicalLeft);
+    if (knownToHaveNoOverflow() && (minLogicalLeft < startLogicalLeft || maxLogicalRight > logicalLeft))
+        clearKnownToHaveNoOverflow();
+    return logicalLeft;
+}
+
+bool InlineFlowBox::requiresIdeographicBaseline(const GlyphOverflowAndFallbackFontsMap& textBoxDataMap) const
+{
+    if (isHorizontal())
+        return false;
+    
+    if (renderer()->style(m_firstLine)->fontDescription().textOrientation() == TextOrientationUpright
+        || renderer()->style(m_firstLine)->font().primaryFont()->hasVerticalGlyphs())
+        return true;
+
+    for (InlineBox* curr = firstChild(); curr; curr = curr->nextOnLine()) {
+        if (curr->renderer()->isPositioned())
+            continue; // Positioned placeholders don't affect calculations.
+        
+        if (curr->isInlineFlowBox()) {
+            if (toInlineFlowBox(curr)->requiresIdeographicBaseline(textBoxDataMap))
+                return true;
+        } else {
+            if (curr->renderer()->style(m_firstLine)->font().primaryFont()->hasVerticalGlyphs())
+                return true;
+            
+            const Vector<const SimpleFontData*>* usedFonts = 0;
+            if (curr->isInlineTextBox()) {
+                GlyphOverflowAndFallbackFontsMap::const_iterator it = textBoxDataMap.find(toInlineTextBox(curr));
+                usedFonts = it == textBoxDataMap.end() ? 0 : &it->second.first;
+            }
+
+            if (usedFonts) {
+                for (size_t i = 0; i < usedFonts->size(); ++i) {
+                    if (usedFonts->at(i)->hasVerticalGlyphs())
+                        return true;
+                }
+            }
+        }
+    }
+    
+    return false;
+}
+
+void InlineFlowBox::adjustMaxAscentAndDescent(LayoutUnit& maxAscent, LayoutUnit& maxDescent, LayoutUnit maxPositionTop, LayoutUnit maxPositionBottom)
+{
+    for (InlineBox* curr = firstChild(); curr; curr = curr->nextOnLine()) {
+        // The computed lineheight needs to be extended for the
+        // positioned elements
+        if (curr->renderer()->isPositioned())
+            continue; // Positioned placeholders don't affect calculations.
+        if (curr->verticalAlign() == TOP || curr->verticalAlign() == BOTTOM) {
+            LayoutUnit lineHeight = curr->lineHeight();
+            if (curr->verticalAlign() == TOP) {
+                if (maxAscent + maxDescent < lineHeight)
+                    maxDescent = lineHeight - maxAscent;
+            }
+            else {
+                if (maxAscent + maxDescent < lineHeight)
+                    maxAscent = lineHeight - maxDescent;
+            }
+
+            if (maxAscent + maxDescent >= max(maxPositionTop, maxPositionBottom))
+                break;
+        }
+
+        if (curr->isInlineFlowBox())
+            toInlineFlowBox(curr)->adjustMaxAscentAndDescent(maxAscent, maxDescent, maxPositionTop, maxPositionBottom);
+    }
+}
+
+void InlineFlowBox::computeLogicalBoxHeights(RootInlineBox* rootBox, LayoutUnit& maxPositionTop, LayoutUnit& maxPositionBottom,
+                                             LayoutUnit& maxAscent, LayoutUnit& maxDescent, bool& setMaxAscent, bool& setMaxDescent,
+                                             bool strictMode, GlyphOverflowAndFallbackFontsMap& textBoxDataMap,
+                                             FontBaseline baselineType, VerticalPositionCache& verticalPositionCache)
+{
+    // The primary purpose of this function is to compute the maximal ascent and descent values for
+    // a line. These values are computed based off the block's line-box-contain property, which indicates
+    // what parts of descendant boxes have to fit within the line.
+    //
+    // The maxAscent value represents the distance of the highest point of any box (typically including line-height) from
+    // the root box's baseline. The maxDescent value represents the distance of the lowest point of any box
+    // (also typically including line-height) from the root box baseline. These values can be negative.
+    //
+    // A secondary purpose of this function is to store the offset of every box's baseline from the root box's
+    // baseline. This information is cached in the logicalTop() of every box. We're effectively just using
+    // the logicalTop() as scratch space.
+    //
+    // Because a box can be positioned such that it ends up fully above or fully below the
+    // root line box, we only consider it to affect the maxAscent and maxDescent values if some
+    // part of the box (EXCLUDING leading) is above (for ascent) or below (for descent) the root box's baseline.
+    bool affectsAscent = false;
+    bool affectsDescent = false;
+    bool checkChildren = !descendantsHaveSameLineHeightAndBaseline();
+    
+    if (isRootInlineBox()) {
+        // Examine our root box.
+        LayoutUnit ascent = 0;
+        LayoutUnit descent = 0;
+        rootBox->ascentAndDescentForBox(rootBox, textBoxDataMap, ascent, descent, affectsAscent, affectsDescent);
+        if (strictMode || hasTextChildren() || (!checkChildren && hasTextDescendants())) {
+            if (maxAscent < ascent || !setMaxAscent) {
+                maxAscent = ascent;
+                setMaxAscent = true;
+            }
+            if (maxDescent < descent || !setMaxDescent) {
+                maxDescent = descent;
+                setMaxDescent = true;
+            }
+        }
+    }
+
+    if (!checkChildren)
+        return;
+
+    for (InlineBox* curr = firstChild(); curr; curr = curr->nextOnLine()) {
+        if (curr->renderer()->isPositioned())
+            continue; // Positioned placeholders don't affect calculations.
+        
+        InlineFlowBox* inlineFlowBox = curr->isInlineFlowBox() ? toInlineFlowBox(curr) : 0;
+        
+        bool affectsAscent = false;
+        bool affectsDescent = false;
+        
+        // The verticalPositionForBox function returns the distance between the child box's baseline
+        // and the root box's baseline.  The value is negative if the child box's baseline is above the
+        // root box's baseline, and it is positive if the child box's baseline is below the root box's baseline.
+        curr->setLogicalTop(rootBox->verticalPositionForBox(curr, verticalPositionCache));
+        
+        LayoutUnit ascent = 0;
+        LayoutUnit descent = 0;
+        rootBox->ascentAndDescentForBox(curr, textBoxDataMap, ascent, descent, affectsAscent, affectsDescent);
+
+        LayoutUnit boxHeight = ascent + descent;
+        if (curr->verticalAlign() == TOP) {
+            if (maxPositionTop < boxHeight)
+                maxPositionTop = boxHeight;
+        } else if (curr->verticalAlign() == BOTTOM) {
+            if (maxPositionBottom < boxHeight)
+                maxPositionBottom = boxHeight;
+        } else if (!inlineFlowBox || strictMode || inlineFlowBox->hasTextChildren() || (inlineFlowBox->descendantsHaveSameLineHeightAndBaseline() && inlineFlowBox->hasTextDescendants())
+                   || inlineFlowBox->boxModelObject()->hasInlineDirectionBordersOrPadding()) {
+            // Note that these values can be negative.  Even though we only affect the maxAscent and maxDescent values
+            // if our box (excluding line-height) was above (for ascent) or below (for descent) the root baseline, once you factor in line-height
+            // the final box can end up being fully above or fully below the root box's baseline!  This is ok, but what it
+            // means is that ascent and descent (including leading), can end up being negative.  The setMaxAscent and
+            // setMaxDescent booleans are used to ensure that we're willing to initially set maxAscent/Descent to negative
+            // values.
+            ascent -= curr->logicalTop();
+            descent += curr->logicalTop();
+            if (affectsAscent && (maxAscent < ascent || !setMaxAscent)) {
+                maxAscent = ascent;
+                setMaxAscent = true;
+            }
+
+            if (affectsDescent && (maxDescent < descent || !setMaxDescent)) {
+                maxDescent = descent;
+                setMaxDescent = true;
+            }
+        }
+
+        if (inlineFlowBox)
+            inlineFlowBox->computeLogicalBoxHeights(rootBox, maxPositionTop, maxPositionBottom, maxAscent, maxDescent,
+                                                    setMaxAscent, setMaxDescent, strictMode, textBoxDataMap,
+                                                    baselineType, verticalPositionCache);
+    }
+}
+
+void InlineFlowBox::placeBoxesInBlockDirection(LayoutUnit top, LayoutUnit maxHeight, LayoutUnit maxAscent, bool strictMode, LayoutUnit& lineTop, LayoutUnit& lineBottom, bool& setLineTop,
+                                               LayoutUnit& lineTopIncludingMargins, LayoutUnit& lineBottomIncludingMargins, bool& hasAnnotationsBefore, bool& hasAnnotationsAfter, FontBaseline baselineType)
+{
+    bool isRootBox = isRootInlineBox();
+    if (isRootBox) {
+        const FontMetrics& fontMetrics = renderer()->style(m_firstLine)->fontMetrics();
+        setLogicalTop(top + maxAscent - fontMetrics.ascent(baselineType));
+    }
+
+    LayoutUnit adjustmentForChildrenWithSameLineHeightAndBaseline = 0;
+    if (descendantsHaveSameLineHeightAndBaseline()) {
+        adjustmentForChildrenWithSameLineHeightAndBaseline = logicalTop();
+        if (parent())
+            adjustmentForChildrenWithSameLineHeightAndBaseline += (boxModelObject()->borderBefore() + boxModelObject()->paddingBefore());
+    }
+
+    for (InlineBox* curr = firstChild(); curr; curr = curr->nextOnLine()) {
+        if (curr->renderer()->isPositioned())
+            continue; // Positioned placeholders don't affect calculations.
+
+        if (descendantsHaveSameLineHeightAndBaseline()) {
+            curr->adjustBlockDirectionPosition(adjustmentForChildrenWithSameLineHeightAndBaseline);
+            continue;
+        }
+
+        InlineFlowBox* inlineFlowBox = curr->isInlineFlowBox() ? toInlineFlowBox(curr) : 0;
+        bool childAffectsTopBottomPos = true;
+        if (curr->verticalAlign() == TOP)
+            curr->setLogicalTop(top);
+        else if (curr->verticalAlign() == BOTTOM)
+            curr->setLogicalTop(top + maxHeight - curr->lineHeight());
+        else {
+            if (!strictMode && inlineFlowBox && !inlineFlowBox->hasTextChildren() && !curr->boxModelObject()->hasInlineDirectionBordersOrPadding()
+                && !(inlineFlowBox->descendantsHaveSameLineHeightAndBaseline() && inlineFlowBox->hasTextDescendants()))
+                childAffectsTopBottomPos = false;
+            LayoutUnit posAdjust = maxAscent - curr->baselinePosition(baselineType);
+            curr->setLogicalTop(curr->logicalTop() + top + posAdjust);
+        }
+        
+        LayoutUnit newLogicalTop = curr->logicalTop();
+        LayoutUnit newLogicalTopIncludingMargins = newLogicalTop;
+        LayoutUnit boxHeight = curr->logicalHeight();
+        LayoutUnit boxHeightIncludingMargins = boxHeight;
+            
+        if (curr->isText() || curr->isInlineFlowBox()) {
+            const FontMetrics& fontMetrics = curr->renderer()->style(m_firstLine)->fontMetrics();
+            newLogicalTop += curr->baselinePosition(baselineType) - fontMetrics.ascent(baselineType);
+            if (curr->isInlineFlowBox()) {
+                RenderBoxModelObject* boxObject = toRenderBoxModelObject(curr->renderer());
+                newLogicalTop -= boxObject->style(m_firstLine)->isHorizontalWritingMode() ? boxObject->borderTop() + boxObject->paddingTop() : 
+                                 boxObject->borderRight() + boxObject->paddingRight();
+            }
+            newLogicalTopIncludingMargins = newLogicalTop;
+        } else if (!curr->renderer()->isBR()) {
+            RenderBox* box = toRenderBox(curr->renderer());
+            newLogicalTopIncludingMargins = newLogicalTop;
+            LayoutUnit overSideMargin = curr->isHorizontal() ? box->marginTop() : box->marginRight();
+            LayoutUnit underSideMargin = curr->isHorizontal() ? box->marginBottom() : box->marginLeft();
+            newLogicalTop += overSideMargin;
+            boxHeightIncludingMargins += overSideMargin + underSideMargin;
+        }
+
+        curr->setLogicalTop(newLogicalTop);
+
+        if (childAffectsTopBottomPos) {
+            if (curr->renderer()->isRubyRun()) {
+                // Treat the leading on the first and last lines of ruby runs as not being part of the overall lineTop/lineBottom.
+                // Really this is a workaround hack for the fact that ruby should have been done as line layout and not done using
+                // inline-block.
+                if (!renderer()->style()->isFlippedLinesWritingMode())
+                    hasAnnotationsBefore = true;
+                else
+                    hasAnnotationsAfter = true;
+
+                RenderRubyRun* rubyRun = toRenderRubyRun(curr->renderer());
+                if (RenderRubyBase* rubyBase = rubyRun->rubyBase()) {
+                    LayoutUnit bottomRubyBaseLeading = (curr->logicalHeight() - rubyBase->logicalBottom()) + rubyBase->logicalHeight() - (rubyBase->lastRootBox() ? rubyBase->lastRootBox()->lineBottom() : 0);
+                    LayoutUnit topRubyBaseLeading = rubyBase->logicalTop() + (rubyBase->firstRootBox() ? rubyBase->firstRootBox()->lineTop() : 0);
+                    newLogicalTop += !renderer()->style()->isFlippedLinesWritingMode() ? topRubyBaseLeading : bottomRubyBaseLeading;
+                    boxHeight -= (topRubyBaseLeading + bottomRubyBaseLeading);
+                }
+            }
+            if (curr->isInlineTextBox()) {
+                TextEmphasisPosition emphasisMarkPosition;
+                if (toInlineTextBox(curr)->getEmphasisMarkPosition(curr->renderer()->style(m_firstLine), emphasisMarkPosition)) {
+                    bool emphasisMarkIsOver = emphasisMarkPosition == TextEmphasisPositionOver;
+                    if (emphasisMarkIsOver != curr->renderer()->style(m_firstLine)->isFlippedLinesWritingMode())
+                        hasAnnotationsBefore = true;
+                    else
+                        hasAnnotationsAfter = true;
+                }
+            }
+
+            if (!setLineTop) {
+                setLineTop = true;
+                lineTop = newLogicalTop;
+                lineTopIncludingMargins = min(lineTop, newLogicalTopIncludingMargins);
+            } else {
+                lineTop = min(lineTop, newLogicalTop);
+                lineTopIncludingMargins = min(lineTop, min(lineTopIncludingMargins, newLogicalTopIncludingMargins));
+            }
+            lineBottom = max(lineBottom, newLogicalTop + boxHeight);
+            lineBottomIncludingMargins = max(lineBottom, max(lineBottomIncludingMargins, newLogicalTopIncludingMargins + boxHeightIncludingMargins));
+        }
+
+        // Adjust boxes to use their real box y/height and not the logical height (as dictated by
+        // line-height).
+        if (inlineFlowBox)
+            inlineFlowBox->placeBoxesInBlockDirection(top, maxHeight, maxAscent, strictMode, lineTop, lineBottom, setLineTop,
+                                                      lineTopIncludingMargins, lineBottomIncludingMargins, hasAnnotationsBefore, hasAnnotationsAfter, baselineType);
+    }
+
+    if (isRootBox) {
+        if (strictMode || hasTextChildren() || (descendantsHaveSameLineHeightAndBaseline() && hasTextDescendants())) {
+            if (!setLineTop) {
+                setLineTop = true;
+                lineTop = pixelSnappedLogicalTop();
+                lineTopIncludingMargins = lineTop;
+            } else {
+                lineTop = min(lineTop, pixelSnappedLogicalTop());
+                lineTopIncludingMargins = min(lineTop, lineTopIncludingMargins);
+            }
+            lineBottom = max(lineBottom, pixelSnappedLogicalBottom());
+            lineBottomIncludingMargins = max(lineBottom, lineBottomIncludingMargins);
+        }
+        
+        if (renderer()->style()->isFlippedLinesWritingMode())
+            flipLinesInBlockDirection(lineTopIncludingMargins, lineBottomIncludingMargins);
+    }
+}
+
+void InlineFlowBox::flipLinesInBlockDirection(LayoutUnit lineTop, LayoutUnit lineBottom)
+{
+    // Flip the box on the line such that the top is now relative to the lineBottom instead of the lineTop.
+    setLogicalTop(lineBottom - (logicalTop() - lineTop) - logicalHeight());
+    
+    for (InlineBox* curr = firstChild(); curr; curr = curr->nextOnLine()) {
+        if (curr->renderer()->isPositioned())
+            continue; // Positioned placeholders aren't affected here.
+        
+        if (curr->isInlineFlowBox())
+            toInlineFlowBox(curr)->flipLinesInBlockDirection(lineTop, lineBottom);
+        else
+            curr->setLogicalTop(lineBottom - (curr->logicalTop() - lineTop) - curr->logicalHeight());
+    }
+}
+
+inline void InlineFlowBox::addBoxShadowVisualOverflow(LayoutRect& logicalVisualOverflow)
+{
+    // box-shadow on root line boxes is applying to the block and not to the lines.
+    if (!parent())
+        return;
+
+    RenderStyle* style = renderer()->style(m_firstLine);
+    if (!style->boxShadow())
+        return;
+
+    LayoutUnit boxShadowLogicalTop;
+    LayoutUnit boxShadowLogicalBottom;
+    style->getBoxShadowBlockDirectionExtent(boxShadowLogicalTop, boxShadowLogicalBottom);
+    
+    // Similar to how glyph overflow works, if our lines are flipped, then it's actually the opposite shadow that applies, since
+    // the line is "upside down" in terms of block coordinates.
+    LayoutUnit shadowLogicalTop = style->isFlippedLinesWritingMode() ? -boxShadowLogicalBottom : boxShadowLogicalTop;
+    LayoutUnit shadowLogicalBottom = style->isFlippedLinesWritingMode() ? -boxShadowLogicalTop : boxShadowLogicalBottom;
+    
+    LayoutUnit logicalTopVisualOverflow = min(pixelSnappedLogicalTop() + shadowLogicalTop, logicalVisualOverflow.y());
+    LayoutUnit logicalBottomVisualOverflow = max(pixelSnappedLogicalBottom() + shadowLogicalBottom, logicalVisualOverflow.maxY());
+    
+    LayoutUnit boxShadowLogicalLeft;
+    LayoutUnit boxShadowLogicalRight;
+    style->getBoxShadowInlineDirectionExtent(boxShadowLogicalLeft, boxShadowLogicalRight);
+
+    LayoutUnit logicalLeftVisualOverflow = min(pixelSnappedLogicalLeft() + boxShadowLogicalLeft, logicalVisualOverflow.x());
+    LayoutUnit logicalRightVisualOverflow = max(pixelSnappedLogicalRight() + boxShadowLogicalRight, logicalVisualOverflow.maxX());
+    
+    logicalVisualOverflow = LayoutRect(logicalLeftVisualOverflow, logicalTopVisualOverflow,
+                                       logicalRightVisualOverflow - logicalLeftVisualOverflow, logicalBottomVisualOverflow - logicalTopVisualOverflow);
+}
+
+inline void InlineFlowBox::addBorderOutsetVisualOverflow(LayoutRect& logicalVisualOverflow)
+{
+    // border-image-outset on root line boxes is applying to the block and not to the lines.
+    if (!parent())
+        return;
+    
+    RenderStyle* style = renderer()->style(m_firstLine);
+    if (!style->hasBorderImageOutsets())
+        return;
+    
+    LayoutUnit borderOutsetLogicalTop;
+    LayoutUnit borderOutsetLogicalBottom;
+    style->getBorderImageBlockDirectionOutsets(borderOutsetLogicalTop, borderOutsetLogicalBottom);
+
+    // Similar to how glyph overflow works, if our lines are flipped, then it's actually the opposite border that applies, since
+    // the line is "upside down" in terms of block coordinates. vertical-rl and horizontal-bt are the flipped line modes.
+    LayoutUnit outsetLogicalTop = style->isFlippedLinesWritingMode() ? borderOutsetLogicalBottom : borderOutsetLogicalTop;
+    LayoutUnit outsetLogicalBottom = style->isFlippedLinesWritingMode() ? borderOutsetLogicalTop : borderOutsetLogicalBottom;
+
+    LayoutUnit logicalTopVisualOverflow = min(pixelSnappedLogicalTop() - outsetLogicalTop, logicalVisualOverflow.y());
+    LayoutUnit logicalBottomVisualOverflow = max(pixelSnappedLogicalBottom() + outsetLogicalBottom, logicalVisualOverflow.maxY());
+    
+    LayoutUnit borderOutsetLogicalLeft;
+    LayoutUnit borderOutsetLogicalRight;
+    style->getBorderImageInlineDirectionOutsets(borderOutsetLogicalLeft, borderOutsetLogicalRight);
+
+    LayoutUnit outsetLogicalLeft = includeLogicalLeftEdge() ? borderOutsetLogicalLeft : 0;
+    LayoutUnit outsetLogicalRight = includeLogicalRightEdge() ? borderOutsetLogicalRight : 0;
+
+    LayoutUnit logicalLeftVisualOverflow = min(pixelSnappedLogicalLeft() - outsetLogicalLeft, logicalVisualOverflow.x());
+    LayoutUnit logicalRightVisualOverflow = max(pixelSnappedLogicalRight() + outsetLogicalRight, logicalVisualOverflow.maxX());
+    
+    logicalVisualOverflow = LayoutRect(logicalLeftVisualOverflow, logicalTopVisualOverflow,
+                                       logicalRightVisualOverflow - logicalLeftVisualOverflow, logicalBottomVisualOverflow - logicalTopVisualOverflow);
+}
+
+inline void InlineFlowBox::addTextBoxVisualOverflow(InlineTextBox* textBox, GlyphOverflowAndFallbackFontsMap& textBoxDataMap, LayoutRect& logicalVisualOverflow)
+{
+    if (textBox->knownToHaveNoOverflow())
+        return;
+
+    RenderStyle* style = textBox->renderer()->style(m_firstLine);
+    
+    GlyphOverflowAndFallbackFontsMap::iterator it = textBoxDataMap.find(textBox);
+    GlyphOverflow* glyphOverflow = it == textBoxDataMap.end() ? 0 : &it->second.second;
+    bool isFlippedLine = style->isFlippedLinesWritingMode();
+
+    int topGlyphEdge = glyphOverflow ? (isFlippedLine ? glyphOverflow->bottom : glyphOverflow->top) : 0;
+    int bottomGlyphEdge = glyphOverflow ? (isFlippedLine ? glyphOverflow->top : glyphOverflow->bottom) : 0;
+    int leftGlyphEdge = glyphOverflow ? glyphOverflow->left : 0;
+    int rightGlyphEdge = glyphOverflow ? glyphOverflow->right : 0;
+
+    int strokeOverflow = static_cast<int>(ceilf(style->textStrokeWidth() / 2.0f));
+    int topGlyphOverflow = -strokeOverflow - topGlyphEdge;
+    int bottomGlyphOverflow = strokeOverflow + bottomGlyphEdge;
+    int leftGlyphOverflow = -strokeOverflow - leftGlyphEdge;
+    int rightGlyphOverflow = strokeOverflow + rightGlyphEdge;
+
+    TextEmphasisPosition emphasisMarkPosition;
+    if (style->textEmphasisMark() != TextEmphasisMarkNone && textBox->getEmphasisMarkPosition(style, emphasisMarkPosition)) {
+        int emphasisMarkHeight = style->font().emphasisMarkHeight(style->textEmphasisMarkString());
+        if ((emphasisMarkPosition == TextEmphasisPositionOver) == (!style->isFlippedLinesWritingMode()))
+            topGlyphOverflow = min(topGlyphOverflow, -emphasisMarkHeight);
+        else
+            bottomGlyphOverflow = max(bottomGlyphOverflow, emphasisMarkHeight);
+    }
+
+    // If letter-spacing is negative, we should factor that into right layout overflow. (Even in RTL, letter-spacing is
+    // applied to the right, so this is not an issue with left overflow.
+    rightGlyphOverflow -= min(0, (int)style->font().letterSpacing());
+
+    LayoutUnit textShadowLogicalTop;
+    LayoutUnit textShadowLogicalBottom;
+    style->getTextShadowBlockDirectionExtent(textShadowLogicalTop, textShadowLogicalBottom);
+    
+    LayoutUnit childOverflowLogicalTop = min<LayoutUnit>(textShadowLogicalTop + topGlyphOverflow, topGlyphOverflow);
+    LayoutUnit childOverflowLogicalBottom = max<LayoutUnit>(textShadowLogicalBottom + bottomGlyphOverflow, bottomGlyphOverflow);
+   
+    LayoutUnit textShadowLogicalLeft;
+    LayoutUnit textShadowLogicalRight;
+    style->getTextShadowInlineDirectionExtent(textShadowLogicalLeft, textShadowLogicalRight);
+   
+    LayoutUnit childOverflowLogicalLeft = min<LayoutUnit>(textShadowLogicalLeft + leftGlyphOverflow, leftGlyphOverflow);
+    LayoutUnit childOverflowLogicalRight = max<LayoutUnit>(textShadowLogicalRight + rightGlyphOverflow, rightGlyphOverflow);
+
+    LayoutUnit logicalTopVisualOverflow = min(textBox->pixelSnappedLogicalTop() + childOverflowLogicalTop, logicalVisualOverflow.y());
+    LayoutUnit logicalBottomVisualOverflow = max(textBox->pixelSnappedLogicalBottom() + childOverflowLogicalBottom, logicalVisualOverflow.maxY());
+    LayoutUnit logicalLeftVisualOverflow = min(textBox->pixelSnappedLogicalLeft() + childOverflowLogicalLeft, logicalVisualOverflow.x());
+    LayoutUnit logicalRightVisualOverflow = max(textBox->pixelSnappedLogicalRight() + childOverflowLogicalRight, logicalVisualOverflow.maxX());
+    
+    logicalVisualOverflow = LayoutRect(logicalLeftVisualOverflow, logicalTopVisualOverflow,
+                                       logicalRightVisualOverflow - logicalLeftVisualOverflow, logicalBottomVisualOverflow - logicalTopVisualOverflow);
+                                    
+    textBox->setLogicalOverflowRect(logicalVisualOverflow);
+}
+
+inline void InlineFlowBox::addReplacedChildOverflow(const InlineBox* inlineBox, LayoutRect& logicalLayoutOverflow, LayoutRect& logicalVisualOverflow)
+{
+    RenderBox* box = toRenderBox(inlineBox->renderer());
+    
+    // Visual overflow only propagates if the box doesn't have a self-painting layer.  This rectangle does not include
+    // transforms or relative positioning (since those objects always have self-painting layers), but it does need to be adjusted
+    // for writing-mode differences.
+    if (!box->hasSelfPaintingLayer()) {
+        LayoutRect childLogicalVisualOverflow = box->logicalVisualOverflowRectForPropagation(renderer()->style());
+        childLogicalVisualOverflow.move(inlineBox->logicalLeft(), inlineBox->logicalTop());
+        logicalVisualOverflow.unite(childLogicalVisualOverflow);
+    }
+
+    // Layout overflow internal to the child box only propagates if the child box doesn't have overflow clip set.
+    // Otherwise the child border box propagates as layout overflow.  This rectangle must include transforms and relative positioning
+    // and be adjusted for writing-mode differences.
+    LayoutRect childLogicalLayoutOverflow = box->logicalLayoutOverflowRectForPropagation(renderer()->style());
+    childLogicalLayoutOverflow.move(inlineBox->logicalLeft(), inlineBox->logicalTop());
+    logicalLayoutOverflow.unite(childLogicalLayoutOverflow);
+}
+
+void InlineFlowBox::computeOverflow(LayoutUnit lineTop, LayoutUnit lineBottom, GlyphOverflowAndFallbackFontsMap& textBoxDataMap)
+{
+    // If we know we have no overflow, we can just bail.
+    if (knownToHaveNoOverflow())
+        return;
+
+    // Visual overflow just includes overflow for stuff we need to repaint ourselves.  Self-painting layers are ignored.
+    // Layout overflow is used to determine scrolling extent, so it still includes child layers and also factors in
+    // transforms, relative positioning, etc.
+    LayoutRect logicalLayoutOverflow(enclosingLayoutRect(logicalFrameRectIncludingLineHeight(lineTop, lineBottom)));
+    LayoutRect logicalVisualOverflow(logicalLayoutOverflow);
+  
+    addBoxShadowVisualOverflow(logicalVisualOverflow);
+    addBorderOutsetVisualOverflow(logicalVisualOverflow);
+
+    for (InlineBox* curr = firstChild(); curr; curr = curr->nextOnLine()) {
+        if (curr->renderer()->isPositioned())
+            continue; // Positioned placeholders don't affect calculations.
+        
+        if (curr->renderer()->isText()) {
+            InlineTextBox* text = toInlineTextBox(curr);
+            RenderText* rt = toRenderText(text->renderer());
+            if (rt->isBR())
+                continue;
+            LayoutRect textBoxOverflow(enclosingLayoutRect(text->logicalFrameRect()));
+            addTextBoxVisualOverflow(text, textBoxDataMap, textBoxOverflow);
+            logicalVisualOverflow.unite(textBoxOverflow);
+        } else  if (curr->renderer()->isRenderInline()) {
+            InlineFlowBox* flow = toInlineFlowBox(curr);
+            flow->computeOverflow(lineTop, lineBottom, textBoxDataMap);
+            if (!flow->boxModelObject()->hasSelfPaintingLayer())
+                logicalVisualOverflow.unite(flow->logicalVisualOverflowRect(lineTop, lineBottom));
+            LayoutRect childLayoutOverflow = flow->logicalLayoutOverflowRect(lineTop, lineBottom);
+            childLayoutOverflow.move(flow->boxModelObject()->relativePositionLogicalOffset());
+            logicalLayoutOverflow.unite(childLayoutOverflow);
+        } else
+            addReplacedChildOverflow(curr, logicalLayoutOverflow, logicalVisualOverflow);
+    }
+    
+    setOverflowFromLogicalRects(logicalLayoutOverflow, logicalVisualOverflow, lineTop, lineBottom);
+}
+
+void InlineFlowBox::setLayoutOverflow(const LayoutRect& rect, LayoutUnit lineTop, LayoutUnit lineBottom)
+{
+    LayoutRect frameBox = enclosingLayoutRect(frameRectIncludingLineHeight(lineTop, lineBottom));
+    if (frameBox.contains(rect) || rect.isEmpty())
+        return;
+
+    if (!m_overflow)
+        m_overflow = adoptPtr(new RenderOverflow(frameBox, frameBox));
+    
+    m_overflow->setLayoutOverflow(rect);
+}
+
+void InlineFlowBox::setVisualOverflow(const LayoutRect& rect, LayoutUnit lineTop, LayoutUnit lineBottom)
+{
+    LayoutRect frameBox = enclosingLayoutRect(frameRectIncludingLineHeight(lineTop, lineBottom));
+    if (frameBox.contains(rect) || rect.isEmpty())
+        return;
+        
+    if (!m_overflow)
+        m_overflow = adoptPtr(new RenderOverflow(frameBox, frameBox));
+    
+    m_overflow->setVisualOverflow(rect);
+}
+
+void InlineFlowBox::setOverflowFromLogicalRects(const LayoutRect& logicalLayoutOverflow, const LayoutRect& logicalVisualOverflow, LayoutUnit lineTop, LayoutUnit lineBottom)
+{
+    LayoutRect layoutOverflow(isHorizontal() ? logicalLayoutOverflow : logicalLayoutOverflow.transposedRect());
+    setLayoutOverflow(layoutOverflow, lineTop, lineBottom);
+    
+    LayoutRect visualOverflow(isHorizontal() ? logicalVisualOverflow : logicalVisualOverflow.transposedRect());
+    setVisualOverflow(visualOverflow, lineTop, lineBottom);
+}
+
+bool InlineFlowBox::nodeAtPoint(const HitTestRequest& request, HitTestResult& result, const LayoutPoint& pointInContainer, const LayoutPoint& accumulatedOffset, LayoutUnit lineTop, LayoutUnit lineBottom)
+{
+    LayoutRect overflowRect(visualOverflowRect(lineTop, lineBottom));
+    flipForWritingMode(overflowRect);
+    overflowRect.moveBy(accumulatedOffset);
+    if (!overflowRect.intersects(result.rectForPoint(pointInContainer)))
+        return false;
+
+    // Check children first.
+    for (InlineBox* curr = lastChild(); curr; curr = curr->prevOnLine()) {
+        if ((curr->renderer()->isText() || !curr->boxModelObject()->hasSelfPaintingLayer()) && curr->nodeAtPoint(request, result, pointInContainer, accumulatedOffset, lineTop, lineBottom)) {
+            renderer()->updateHitTestResult(result, pointInContainer - toLayoutSize(accumulatedOffset));
+            return true;
+        }
+    }
+
+    // Now check ourselves. Pixel snap hit testing.
+    LayoutRect frameRect = roundedFrameRect();
+    LayoutUnit minX = frameRect.x();
+    LayoutUnit minY = frameRect.y();
+    LayoutUnit width = frameRect.width();
+    LayoutUnit height = frameRect.height();
+
+    // Constrain our hit testing to the line top and bottom if necessary.
+    bool noQuirksMode = renderer()->document()->inNoQuirksMode();
+    if (!noQuirksMode && !hasTextChildren() && !(descendantsHaveSameLineHeightAndBaseline() && hasTextDescendants())) {
+        RootInlineBox* rootBox = root();
+        LayoutUnit& top = isHorizontal() ? minY : minX;
+        LayoutUnit& logicalHeight = isHorizontal() ? height : width;
+        LayoutUnit bottom = min(rootBox->lineBottom(), top + logicalHeight);
+        top = max(rootBox->lineTop(), top);
+        logicalHeight = bottom - top;
+    }
+    
+    // Move x/y to our coordinates.
+    LayoutRect rect(minX, minY, width, height);
+    flipForWritingMode(rect);
+    rect.moveBy(accumulatedOffset);
+
+    if (visibleToHitTesting() && rect.intersects(result.rectForPoint(pointInContainer))) {
+        renderer()->updateHitTestResult(result, flipForWritingMode(pointInContainer - toLayoutSize(accumulatedOffset))); // Don't add in m_x or m_y here, we want coords in the containing block's space.
+        if (!result.addNodeToRectBasedTestResult(renderer()->node(), pointInContainer, rect))
+            return true;
+    }
+    
+    return false;
+}
+
+void InlineFlowBox::paint(PaintInfo& paintInfo, const LayoutPoint& paintOffset, LayoutUnit lineTop, LayoutUnit lineBottom)
+{
+    LayoutRect overflowRect(visualOverflowRect(lineTop, lineBottom));
+    overflowRect.inflate(renderer()->maximalOutlineSize(paintInfo.phase));
+    flipForWritingMode(overflowRect);
+    overflowRect.moveBy(paintOffset);
+    
+    if (!paintInfo.rect.intersects(overflowRect))
+        return;
+
+    if (paintInfo.phase != PaintPhaseChildOutlines) {
+        if (paintInfo.phase == PaintPhaseOutline || paintInfo.phase == PaintPhaseSelfOutline) {
+            // Add ourselves to the paint info struct's list of inlines that need to paint their
+            // outlines.
+            if (renderer()->style()->visibility() == VISIBLE && renderer()->hasOutline() && !isRootInlineBox()) {
+                RenderInline* inlineFlow = toRenderInline(renderer());
+
+                RenderBlock* cb = 0;
+                bool containingBlockPaintsContinuationOutline = inlineFlow->continuation() || inlineFlow->isInlineElementContinuation();
+                if (containingBlockPaintsContinuationOutline) {           
+                    // FIXME: See https://bugs.webkit.org/show_bug.cgi?id=54690. We currently don't reconnect inline continuations
+                    // after a child removal. As a result, those merged inlines do not get seperated and hence not get enclosed by
+                    // anonymous blocks. In this case, it is better to bail out and paint it ourself.
+                    RenderBlock* enclosingAnonymousBlock = renderer()->containingBlock();
+                    if (!enclosingAnonymousBlock->isAnonymousBlock())
+                        containingBlockPaintsContinuationOutline = false;
+                    else {
+                        cb = enclosingAnonymousBlock->containingBlock();
+                        for (RenderBoxModelObject* box = boxModelObject(); box != cb; box = box->parent()->enclosingBoxModelObject()) {
+                            if (box->hasSelfPaintingLayer()) {
+                                containingBlockPaintsContinuationOutline = false;
+                                break;
+                            }
+                        }
+                    }
+                }
+
+                if (containingBlockPaintsContinuationOutline) {
+                    // Add ourselves to the containing block of the entire continuation so that it can
+                    // paint us atomically.
+                    cb->addContinuationWithOutline(toRenderInline(renderer()->node()->renderer()));
+                } else if (!inlineFlow->isInlineElementContinuation())
+                    paintInfo.outlineObjects->add(inlineFlow);
+            }
+        } else if (paintInfo.phase == PaintPhaseMask) {
+            paintMask(paintInfo, paintOffset);
+            return;
+        } else {
+            // Paint our background, border and box-shadow.
+            paintBoxDecorations(paintInfo, paintOffset);
+        }
+    }
+
+    if (paintInfo.phase == PaintPhaseMask)
+        return;
+
+    PaintPhase paintPhase = paintInfo.phase == PaintPhaseChildOutlines ? PaintPhaseOutline : paintInfo.phase;
+    PaintInfo childInfo(paintInfo);
+    childInfo.phase = paintPhase;
+    childInfo.updatePaintingRootForChildren(renderer());
+    
+    // Paint our children.
+    if (paintPhase != PaintPhaseSelfOutline) {
+        for (InlineBox* curr = firstChild(); curr; curr = curr->nextOnLine()) {
+            if (curr->renderer()->isText() || !curr->boxModelObject()->hasSelfPaintingLayer())
+                curr->paint(childInfo, paintOffset, lineTop, lineBottom);
+        }
+    }
+}
+
+void InlineFlowBox::paintFillLayers(const PaintInfo& paintInfo, const Color& c, const FillLayer* fillLayer, const LayoutRect& rect, CompositeOperator op)
+{
+    if (!fillLayer)
+        return;
+    paintFillLayers(paintInfo, c, fillLayer->next(), rect, op);
+    paintFillLayer(paintInfo, c, fillLayer, rect, op);
+}
+
+void InlineFlowBox::paintFillLayer(const PaintInfo& paintInfo, const Color& c, const FillLayer* fillLayer, const LayoutRect& rect, CompositeOperator op)
+{
+    StyleImage* img = fillLayer->image();
+    bool hasFillImage = img && img->canRender(renderer(), renderer()->style()->effectiveZoom());
+    if ((!hasFillImage && !renderer()->style()->hasBorderRadius()) || (!prevLineBox() && !nextLineBox()) || !parent())
+        boxModelObject()->paintFillLayerExtended(paintInfo, c, fillLayer, rect, BackgroundBleedNone, this, rect.size(), op);
+    else {
+        // We have a fill image that spans multiple lines.
+        // We need to adjust tx and ty by the width of all previous lines.
+        // Think of background painting on inlines as though you had one long line, a single continuous
+        // strip.  Even though that strip has been broken up across multiple lines, you still paint it
+        // as though you had one single line.  This means each line has to pick up the background where
+        // the previous line left off.
+        LayoutUnit logicalOffsetOnLine = 0;
+        LayoutUnit totalLogicalWidth;
+        if (renderer()->style()->direction() == LTR) {
+            for (InlineFlowBox* curr = prevLineBox(); curr; curr = curr->prevLineBox())
+                logicalOffsetOnLine += curr->logicalWidth();
+            totalLogicalWidth = logicalOffsetOnLine;
+            for (InlineFlowBox* curr = this; curr; curr = curr->nextLineBox())
+                totalLogicalWidth += curr->logicalWidth();
+        } else {
+            for (InlineFlowBox* curr = nextLineBox(); curr; curr = curr->nextLineBox())
+                logicalOffsetOnLine += curr->logicalWidth();
+            totalLogicalWidth = logicalOffsetOnLine;
+            for (InlineFlowBox* curr = this; curr; curr = curr->prevLineBox())
+                totalLogicalWidth += curr->logicalWidth();
+        }
+        LayoutUnit stripX = rect.x() - (isHorizontal() ? logicalOffsetOnLine : 0);
+        LayoutUnit stripY = rect.y() - (isHorizontal() ? 0 : logicalOffsetOnLine);
+        LayoutUnit stripWidth = isHorizontal() ? totalLogicalWidth : width();
+        LayoutUnit stripHeight = isHorizontal() ? height() : totalLogicalWidth;
+
+        GraphicsContextStateSaver stateSaver(*paintInfo.context);
+        paintInfo.context->clip(LayoutRect(rect.x(), rect.y(), width(), height()));
+        boxModelObject()->paintFillLayerExtended(paintInfo, c, fillLayer, LayoutRect(stripX, stripY, stripWidth, stripHeight), BackgroundBleedNone, this, rect.size(), op);
+    }
+}
+
+void InlineFlowBox::paintBoxShadow(const PaintInfo& info, RenderStyle* s, ShadowStyle shadowStyle, const LayoutRect& paintRect)
+{
+    if ((!prevLineBox() && !nextLineBox()) || !parent())
+        boxModelObject()->paintBoxShadow(info, paintRect, s, shadowStyle);
+    else {
+        // FIXME: We can do better here in the multi-line case. We want to push a clip so that the shadow doesn't
+        // protrude incorrectly at the edges, and we want to possibly include shadows cast from the previous/following lines
+        boxModelObject()->paintBoxShadow(info, paintRect, s, shadowStyle, includeLogicalLeftEdge(), includeLogicalRightEdge());
+    }
+}
+
+void InlineFlowBox::constrainToLineTopAndBottomIfNeeded(LayoutRect& rect) const
+{
+    bool noQuirksMode = renderer()->document()->inNoQuirksMode();
+    if (!noQuirksMode && !hasTextChildren() && !(descendantsHaveSameLineHeightAndBaseline() && hasTextDescendants())) {
+        const RootInlineBox* rootBox = root();
+        LayoutUnit logicalTop = isHorizontal() ? rect.y() : rect.x();
+        LayoutUnit logicalHeight = isHorizontal() ? rect.height() : rect.width();
+        LayoutUnit bottom = min(rootBox->lineBottom(), logicalTop + logicalHeight);
+        logicalTop = max(rootBox->lineTop(), logicalTop);
+        logicalHeight = bottom - logicalTop;
+        if (isHorizontal()) {
+            rect.setY(logicalTop);
+            rect.setHeight(logicalHeight);
+        } else {
+            rect.setX(logicalTop);
+            rect.setWidth(logicalHeight);
+        }
+    }
+}
+
+static LayoutRect clipRectForNinePieceImageStrip(InlineFlowBox* box, const NinePieceImage& image, const LayoutRect& paintRect)
+{
+    LayoutRect clipRect(paintRect);
+    RenderStyle* style = box->renderer()->style();
+    LayoutUnit topOutset;
+    LayoutUnit rightOutset;
+    LayoutUnit bottomOutset;
+    LayoutUnit leftOutset;
+    style->getImageOutsets(image, topOutset, rightOutset, bottomOutset, leftOutset);
+    if (box->isHorizontal()) {
+        clipRect.setY(paintRect.y() - topOutset);
+        clipRect.setHeight(paintRect.height() + topOutset + bottomOutset);
+        if (box->includeLogicalLeftEdge()) {
+            clipRect.setX(paintRect.x() - leftOutset);
+            clipRect.setWidth(paintRect.width() + leftOutset);
+        }
+        if (box->includeLogicalRightEdge())
+            clipRect.setWidth(clipRect.width() + rightOutset);
+    } else {
+        clipRect.setX(paintRect.x() - leftOutset);
+        clipRect.setWidth(paintRect.width() + leftOutset + rightOutset);
+        if (box->includeLogicalLeftEdge()) {
+            clipRect.setY(paintRect.y() - topOutset);
+            clipRect.setHeight(paintRect.height() + topOutset);
+        }
+        if (box->includeLogicalRightEdge())
+            clipRect.setHeight(clipRect.height() + bottomOutset);
+    }
+    return clipRect;
+}
+
+void InlineFlowBox::paintBoxDecorations(PaintInfo& paintInfo, const LayoutPoint& paintOffset)
+{
+    if (!paintInfo.shouldPaintWithinRoot(renderer()) || renderer()->style()->visibility() != VISIBLE || paintInfo.phase != PaintPhaseForeground)
+        return;
+
+    // Pixel snap background/border painting.
+    LayoutRect frameRect = roundedFrameRect();
+
+    constrainToLineTopAndBottomIfNeeded(frameRect);
+    
+    // Move x/y to our coordinates.
+    LayoutRect localRect(frameRect);
+    flipForWritingMode(localRect);
+    LayoutPoint adjustedPaintoffset = paintOffset + localRect.location();
+    
+    GraphicsContext* context = paintInfo.context;
+    
+    // You can use p::first-line to specify a background. If so, the root line boxes for
+    // a line may actually have to paint a background.
+    RenderStyle* styleToUse = renderer()->style(m_firstLine);
+    if ((!parent() && m_firstLine && styleToUse != renderer()->style()) || (parent() && renderer()->hasBoxDecorations())) {
+        LayoutRect paintRect = LayoutRect(adjustedPaintoffset, frameRect.size());
+        // Shadow comes first and is behind the background and border.
+        paintBoxShadow(paintInfo, styleToUse, Normal, paintRect);
+
+        Color c = styleToUse->visitedDependentColor(CSSPropertyBackgroundColor);
+        paintFillLayers(paintInfo, c, styleToUse->backgroundLayers(), paintRect);
+        paintBoxShadow(paintInfo, styleToUse, Inset, paintRect);
+
+        // :first-line cannot be used to put borders on a line. Always paint borders with our
+        // non-first-line style.
+        if (parent() && renderer()->style()->hasBorder()) {
+            const NinePieceImage& borderImage = renderer()->style()->borderImage();
+            StyleImage* borderImageSource = borderImage.image();
+            bool hasBorderImage = borderImageSource && borderImageSource->canRender(renderer(), styleToUse->effectiveZoom());
+            if (hasBorderImage && !borderImageSource->isLoaded())
+                return; // Don't paint anything while we wait for the image to load.
+
+            // The simple case is where we either have no border image or we are the only box for this object.  In those
+            // cases only a single call to draw is required.
+            if (!hasBorderImage || (!prevLineBox() && !nextLineBox()))
+                boxModelObject()->paintBorder(paintInfo, paintRect, renderer()->style(), BackgroundBleedNone, includeLogicalLeftEdge(), includeLogicalRightEdge());
+            else {
+                // We have a border image that spans multiple lines.
+                // We need to adjust tx and ty by the width of all previous lines.
+                // Think of border image painting on inlines as though you had one long line, a single continuous
+                // strip.  Even though that strip has been broken up across multiple lines, you still paint it
+                // as though you had one single line.  This means each line has to pick up the image where
+                // the previous line left off.
+                // FIXME: What the heck do we do with RTL here? The math we're using is obviously not right,
+                // but it isn't even clear how this should work at all.
+                LayoutUnit logicalOffsetOnLine = 0;
+                for (InlineFlowBox* curr = prevLineBox(); curr; curr = curr->prevLineBox())
+                    logicalOffsetOnLine += curr->logicalWidth();
+                LayoutUnit totalLogicalWidth = logicalOffsetOnLine;
+                for (InlineFlowBox* curr = this; curr; curr = curr->nextLineBox())
+                    totalLogicalWidth += curr->logicalWidth();
+                LayoutUnit stripX = adjustedPaintoffset.x() - (isHorizontal() ? logicalOffsetOnLine : 0);
+                LayoutUnit stripY = adjustedPaintoffset.y() - (isHorizontal() ? 0 : logicalOffsetOnLine);
+                LayoutUnit stripWidth = isHorizontal() ? totalLogicalWidth : frameRect.width();
+                LayoutUnit stripHeight = isHorizontal() ? frameRect.height() : totalLogicalWidth;
+
+                LayoutRect clipRect = clipRectForNinePieceImageStrip(this, borderImage, paintRect);
+                GraphicsContextStateSaver stateSaver(*context);
+                context->clip(clipRect);
+                boxModelObject()->paintBorder(paintInfo, LayoutRect(stripX, stripY, stripWidth, stripHeight), renderer()->style());
+            }
+        }
+    }
+}
+
+void InlineFlowBox::paintMask(PaintInfo& paintInfo, const LayoutPoint& paintOffset)
+{
+    if (!paintInfo.shouldPaintWithinRoot(renderer()) || renderer()->style()->visibility() != VISIBLE || paintInfo.phase != PaintPhaseMask)
+        return;
+
+    // Pixel snap mask painting.
+    LayoutRect frameRect = roundedFrameRect();
+
+    constrainToLineTopAndBottomIfNeeded(frameRect);
+    
+    // Move x/y to our coordinates.
+    LayoutRect localRect(frameRect);
+    flipForWritingMode(localRect);
+    LayoutPoint adjustedPaintOffset = paintOffset + localRect.location();
+
+    const NinePieceImage& maskNinePieceImage = renderer()->style()->maskBoxImage();
+    StyleImage* maskBoxImage = renderer()->style()->maskBoxImage().image();
+
+    // Figure out if we need to push a transparency layer to render our mask.
+    bool pushTransparencyLayer = false;
+    bool compositedMask = renderer()->hasLayer() && boxModelObject()->layer()->hasCompositedMask();
+    CompositeOperator compositeOp = CompositeSourceOver;
+    if (!compositedMask) {
+        if ((maskBoxImage && renderer()->style()->maskLayers()->hasImage()) || renderer()->style()->maskLayers()->next())
+            pushTransparencyLayer = true;
+        
+        compositeOp = CompositeDestinationIn;
+        if (pushTransparencyLayer) {
+            paintInfo.context->setCompositeOperation(CompositeDestinationIn);
+            paintInfo.context->beginTransparencyLayer(1.0f);
+            compositeOp = CompositeSourceOver;
+        }
+    }
+
+    LayoutRect paintRect = LayoutRect(adjustedPaintOffset, frameRect.size());
+    paintFillLayers(paintInfo, Color(), renderer()->style()->maskLayers(), paintRect, compositeOp);
+    
+    bool hasBoxImage = maskBoxImage && maskBoxImage->canRender(renderer(), renderer()->style()->effectiveZoom());
+    if (!hasBoxImage || !maskBoxImage->isLoaded()) {
+        if (pushTransparencyLayer)
+            paintInfo.context->endTransparencyLayer();
+        return; // Don't paint anything while we wait for the image to load.
+    }
+
+    // The simple case is where we are the only box for this object.  In those
+    // cases only a single call to draw is required.
+    if (!prevLineBox() && !nextLineBox()) {
+        boxModelObject()->paintNinePieceImage(paintInfo.context, LayoutRect(adjustedPaintOffset, frameRect.size()), renderer()->style(), maskNinePieceImage, compositeOp);
+    } else {
+        // We have a mask image that spans multiple lines.
+        // We need to adjust _tx and _ty by the width of all previous lines.
+        LayoutUnit logicalOffsetOnLine = 0;
+        for (InlineFlowBox* curr = prevLineBox(); curr; curr = curr->prevLineBox())
+            logicalOffsetOnLine += curr->logicalWidth();
+        LayoutUnit totalLogicalWidth = logicalOffsetOnLine;
+        for (InlineFlowBox* curr = this; curr; curr = curr->nextLineBox())
+            totalLogicalWidth += curr->logicalWidth();
+        LayoutUnit stripX = adjustedPaintOffset.x() - (isHorizontal() ? logicalOffsetOnLine : 0);
+        LayoutUnit stripY = adjustedPaintOffset.y() - (isHorizontal() ? 0 : logicalOffsetOnLine);
+        LayoutUnit stripWidth = isHorizontal() ? totalLogicalWidth : frameRect.width();
+        LayoutUnit stripHeight = isHorizontal() ? frameRect.height() : totalLogicalWidth;
+
+        LayoutRect clipRect = clipRectForNinePieceImageStrip(this, maskNinePieceImage, paintRect);
+        GraphicsContextStateSaver stateSaver(*paintInfo.context);
+        paintInfo.context->clip(clipRect);
+        boxModelObject()->paintNinePieceImage(paintInfo.context, LayoutRect(stripX, stripY, stripWidth, stripHeight), renderer()->style(), maskNinePieceImage, compositeOp);
+    }
+    
+    if (pushTransparencyLayer)
+        paintInfo.context->endTransparencyLayer();
+}
+
+InlineBox* InlineFlowBox::firstLeafChild() const
+{
+    InlineBox* leaf = 0;
+    for (InlineBox* child = firstChild(); child && !leaf; child = child->nextOnLine())
+        leaf = child->isLeaf() ? child : toInlineFlowBox(child)->firstLeafChild();
+    return leaf;
+}
+
+InlineBox* InlineFlowBox::lastLeafChild() const
+{
+    InlineBox* leaf = 0;
+    for (InlineBox* child = lastChild(); child && !leaf; child = child->prevOnLine())
+        leaf = child->isLeaf() ? child : toInlineFlowBox(child)->lastLeafChild();
+    return leaf;
+}
+
+RenderObject::SelectionState InlineFlowBox::selectionState()
+{
+    return RenderObject::SelectionNone;
+}
+
+bool InlineFlowBox::canAccommodateEllipsis(bool ltr, int blockEdge, int ellipsisWidth)
+{
+    for (InlineBox *box = firstChild(); box; box = box->nextOnLine()) {
+        if (!box->canAccommodateEllipsis(ltr, blockEdge, ellipsisWidth))
+            return false;
+    }
+    return true;
+}
+
+float InlineFlowBox::placeEllipsisBox(bool ltr, float blockLeftEdge, float blockRightEdge, float ellipsisWidth, bool& foundBox)
+{
+    float result = -1;
+    // We iterate over all children, the foundBox variable tells us when we've found the
+    // box containing the ellipsis.  All boxes after that one in the flow are hidden.
+    // If our flow is ltr then iterate over the boxes from left to right, otherwise iterate
+    // from right to left. Varying the order allows us to correctly hide the boxes following the ellipsis.
+    InlineBox* box = ltr ? firstChild() : lastChild();
+
+    // NOTE: these will cross after foundBox = true.
+    int visibleLeftEdge = blockLeftEdge;
+    int visibleRightEdge = blockRightEdge;
+
+    while (box) {
+        int currResult = box->placeEllipsisBox(ltr, visibleLeftEdge, visibleRightEdge, ellipsisWidth, foundBox);
+        if (currResult != -1 && result == -1)
+            result = currResult;
+
+        if (ltr) {
+            visibleLeftEdge += box->logicalWidth();
+            box = box->nextOnLine();
+        }
+        else {
+            visibleRightEdge -= box->logicalWidth();
+            box = box->prevOnLine();
+        }
+    }
+    return result;
+}
+
+void InlineFlowBox::clearTruncation()
+{
+    for (InlineBox *box = firstChild(); box; box = box->nextOnLine())
+        box->clearTruncation();
+}
+
+LayoutUnit InlineFlowBox::computeOverAnnotationAdjustment(LayoutUnit allowedPosition) const
+{
+    LayoutUnit result = 0;
+    for (InlineBox* curr = firstChild(); curr; curr = curr->nextOnLine()) {
+        if (curr->renderer()->isPositioned())
+            continue; // Positioned placeholders don't affect calculations.
+        
+        if (curr->isInlineFlowBox())
+            result = max(result, toInlineFlowBox(curr)->computeOverAnnotationAdjustment(allowedPosition));
+        
+        if (curr->renderer()->isReplaced() && curr->renderer()->isRubyRun()) {
+            RenderRubyRun* rubyRun = toRenderRubyRun(curr->renderer());
+            RenderRubyText* rubyText = rubyRun->rubyText();
+            if (!rubyText)
+                continue;
+            
+            if (!rubyRun->style()->isFlippedLinesWritingMode()) {
+                LayoutUnit topOfFirstRubyTextLine = rubyText->logicalTop() + (rubyText->firstRootBox() ? rubyText->firstRootBox()->lineTop() : 0);
+                if (topOfFirstRubyTextLine >= 0)
+                    continue;
+                topOfFirstRubyTextLine += curr->logicalTop();
+                result = max(result, allowedPosition - topOfFirstRubyTextLine);
+            } else {
+                LayoutUnit bottomOfLastRubyTextLine = rubyText->logicalTop() + (rubyText->lastRootBox() ? rubyText->lastRootBox()->lineBottom() : rubyText->logicalHeight());
+                if (bottomOfLastRubyTextLine <= curr->logicalHeight())
+                    continue;
+                bottomOfLastRubyTextLine += curr->logicalTop();
+                result = max(result, bottomOfLastRubyTextLine - allowedPosition);
+            }
+        }
+
+        if (curr->isInlineTextBox()) {
+            RenderStyle* style = curr->renderer()->style(m_firstLine);
+            TextEmphasisPosition emphasisMarkPosition;
+            if (style->textEmphasisMark() != TextEmphasisMarkNone && toInlineTextBox(curr)->getEmphasisMarkPosition(style, emphasisMarkPosition) && emphasisMarkPosition == TextEmphasisPositionOver) {
+                if (!style->isFlippedLinesWritingMode()) {
+                    int topOfEmphasisMark = curr->logicalTop() - style->font().emphasisMarkHeight(style->textEmphasisMarkString());
+                    result = max(result, allowedPosition - topOfEmphasisMark);
+                } else {
+                    int bottomOfEmphasisMark = curr->logicalBottom() + style->font().emphasisMarkHeight(style->textEmphasisMarkString());
+                    result = max(result, bottomOfEmphasisMark - allowedPosition);
+                }
+            }
+        }
+    }
+    return result;
+}
+
+LayoutUnit InlineFlowBox::computeUnderAnnotationAdjustment(LayoutUnit allowedPosition) const
+{
+    LayoutUnit result = 0;
+    for (InlineBox* curr = firstChild(); curr; curr = curr->nextOnLine()) {
+        if (curr->renderer()->isPositioned())
+            continue; // Positioned placeholders don't affect calculations.
+
+        if (curr->isInlineFlowBox())
+            result = max(result, toInlineFlowBox(curr)->computeUnderAnnotationAdjustment(allowedPosition));
+
+        if (curr->isInlineTextBox()) {
+            RenderStyle* style = curr->renderer()->style(m_firstLine);
+            if (style->textEmphasisMark() != TextEmphasisMarkNone && style->textEmphasisPosition() == TextEmphasisPositionUnder) {
+                if (!style->isFlippedLinesWritingMode()) {
+                    LayoutUnit bottomOfEmphasisMark = curr->logicalBottom() + style->font().emphasisMarkHeight(style->textEmphasisMarkString());
+                    result = max(result, bottomOfEmphasisMark - allowedPosition);
+                } else {
+                    LayoutUnit topOfEmphasisMark = curr->logicalTop() - style->font().emphasisMarkHeight(style->textEmphasisMarkString());
+                    result = max(result, allowedPosition - topOfEmphasisMark);
+                }
+            }
+        }
+    }
+    return result;
+}
+
+void InlineFlowBox::collectLeafBoxesInLogicalOrder(Vector<InlineBox*>& leafBoxesInLogicalOrder, CustomInlineBoxRangeReverse customReverseImplementation, void* userData) const
+{
+    InlineBox* leaf = firstLeafChild();
+
+    // FIXME: The reordering code is a copy of parts from BidiResolver::createBidiRunsForLine, operating directly on InlineBoxes, instead of BidiRuns.
+    // Investigate on how this code could possibly be shared.
+    unsigned char minLevel = 128;
+    unsigned char maxLevel = 0;
+
+    // First find highest and lowest levels, and initialize leafBoxesInLogicalOrder with the leaf boxes in visual order.
+    for (; leaf; leaf = leaf->nextLeafChild()) {
+        minLevel = min(minLevel, leaf->bidiLevel());
+        maxLevel = max(maxLevel, leaf->bidiLevel());
+        leafBoxesInLogicalOrder.append(leaf);
+    }
+
+    if (renderer()->style()->rtlOrdering() == VisualOrder)
+        return;
+
+    // Reverse of reordering of the line (L2 according to Bidi spec):
+    // L2. From the highest level found in the text to the lowest odd level on each line,
+    // reverse any contiguous sequence of characters that are at that level or higher.
+
+    // Reversing the reordering of the line is only done up to the lowest odd level.
+    if (!(minLevel % 2))
+        ++minLevel;
+
+    Vector<InlineBox*>::iterator end = leafBoxesInLogicalOrder.end();
+    while (minLevel <= maxLevel) {
+        Vector<InlineBox*>::iterator it = leafBoxesInLogicalOrder.begin();
+        while (it != end) {
+            while (it != end) {
+                if ((*it)->bidiLevel() >= minLevel)
+                    break;
+                ++it;
+            }
+            Vector<InlineBox*>::iterator first = it;
+            while (it != end) {
+                if ((*it)->bidiLevel() < minLevel)
+                    break;
+                ++it;
+            }
+            Vector<InlineBox*>::iterator last = it;
+            if (customReverseImplementation) {
+                ASSERT(userData);
+                (*customReverseImplementation)(userData, first, last);
+            } else
+                std::reverse(first, last);
+        }                
+        ++minLevel;
+    }
+}
+
+#ifndef NDEBUG
+
+const char* InlineFlowBox::boxName() const
+{
+    return "InlineFlowBox";
+}
+
+void InlineFlowBox::showLineTreeAndMark(const InlineBox* markedBox1, const char* markedLabel1, const InlineBox* markedBox2, const char* markedLabel2, const RenderObject* obj, int depth) const
+{
+    InlineBox::showLineTreeAndMark(markedBox1, markedLabel1, markedBox2, markedLabel2, obj, depth);
+    for (const InlineBox* box = firstChild(); box; box = box->nextOnLine())
+        box->showLineTreeAndMark(markedBox1, markedLabel1, markedBox2, markedLabel2, obj, depth + 1);
+}
+
+void InlineFlowBox::checkConsistency() const
+{
+#ifdef CHECK_CONSISTENCY
+    ASSERT(!m_hasBadChildList);
+    const InlineBox* prev = 0;
+    for (const InlineBox* child = m_firstChild; child; child = child->nextOnLine()) {
+        ASSERT(child->parent() == this);
+        ASSERT(child->prevOnLine() == prev);
+        prev = child;
+    }
+    ASSERT(prev == m_lastChild);
+#endif
+}
+
+#endif
+
+} // namespace WebCore