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diff --git a/chromium/ui/gfx/color_utils.h b/chromium/ui/gfx/color_utils.h
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+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef UI_GFX_COLOR_UTILS_H_
+#define UI_GFX_COLOR_UTILS_H_
+
+#include "base/basictypes.h"
+#include "third_party/skia/include/core/SkColor.h"
+#include "ui/base/ui_export.h"
+
+class SkBitmap;
+
+namespace color_utils {
+
+// Represents an HSL color.
+struct HSL {
+  double h;
+  double s;
+  double l;
+};
+
+UI_EXPORT unsigned char GetLuminanceForColor(SkColor color);
+
+// Calculated according to http://www.w3.org/TR/WCAG20/#relativeluminancedef
+UI_EXPORT double RelativeLuminance(SkColor color);
+
+// Note: these transformations assume sRGB as the source color space
+UI_EXPORT void SkColorToHSL(SkColor c, HSL* hsl);
+UI_EXPORT SkColor HSLToSkColor(const HSL& hsl, SkAlpha alpha);
+
+// HSL-Shift an SkColor. The shift values are in the range of 0-1, with the
+// option to specify -1 for 'no change'. The shift values are defined as:
+// hsl_shift[0] (hue): The absolute hue value - 0 and 1 map
+//    to 0 and 360 on the hue color wheel (red).
+// hsl_shift[1] (saturation): A saturation shift, with the
+//    following key values:
+//    0 = remove all color.
+//    0.5 = leave unchanged.
+//    1 = fully saturate the image.
+// hsl_shift[2] (lightness): A lightness shift, with the
+//    following key values:
+//    0 = remove all lightness (make all pixels black).
+//    0.5 = leave unchanged.
+//    1 = full lightness (make all pixels white).
+UI_EXPORT SkColor HSLShift(SkColor color, const HSL& shift);
+
+// Determine if a given alpha value is nearly completely transparent.
+bool IsColorCloseToTransparent(SkAlpha alpha);
+
+// Determine if a color is near grey.
+bool IsColorCloseToGrey(int r, int g, int b);
+
+// Builds a histogram based on the Y' of the Y'UV representation of
+// this image.
+UI_EXPORT void BuildLumaHistogram(const SkBitmap& bitmap, int histogram[256]);
+
+// Returns a blend of the supplied colors, ranging from |background| (for
+// |alpha| == 0) to |foreground| (for |alpha| == 255). The alpha channels of
+// the supplied colors are also taken into account, so the returned color may
+// be partially transparent.
+UI_EXPORT SkColor AlphaBlend(SkColor foreground, SkColor background,
+                             SkAlpha alpha);
+
+// Makes a dark color lighter or a light color darker by blending |color| with
+// white or black depending on its current luminance.  |alpha| controls the
+// amount of white or black that will be alpha-blended into |color|.
+UI_EXPORT SkColor BlendTowardOppositeLuminance(SkColor color, SkAlpha alpha);
+
+// Given an opaque foreground and background color, try to return a foreground
+// color that is "readable" over the background color by luma-inverting the
+// foreground color and then picking whichever foreground color has higher
+// contrast against the background color.  You should not pass colors with
+// non-255 alpha to this routine, since determining the correct behavior in such
+// cases can be impossible.
+//
+// NOTE: This won't do anything but waste time if the supplied foreground color
+// has a luma value close to the midpoint (0.5 in the HSL representation).
+UI_EXPORT SkColor GetReadableColor(SkColor foreground, SkColor background);
+
+// Invert a color.
+UI_EXPORT SkColor InvertColor(SkColor color);
+
+// Gets a Windows system color as a SkColor
+UI_EXPORT SkColor GetSysSkColor(int which);
+
+}  // namespace color_utils
+
+#endif  // UI_GFX_COLOR_UTILS_H_