Fix double clicks needing three presses in QWebEngineView

Since Qt 5.3 QWidget has the same behavior as Qt 4 where it will
replace a second MouseButtonPress event with a MouseButtonDblClick
instead of sending both.

Fix the issue by moving the MouseButtonDblClick ignore code up to the
QtQuick code, assume that upper layers will not send
MouseButtonDblClick events, and re-replace the MouseButtonDblClick
event with a MouseButtonPress in the QtWidgets code.

Change-Id: I529dad2de538f486b00eb900ea6d2ed849a3b1f0
Reviewed-by: Andras Becsi <andras.becsi@digia.com>

4 files changed, 15 insertions, 13 deletions

diff --git a/src/core/render_widget_host_view_qt.cpp b/src/core/render_widget_host_view_qt.cpp
index fa3fe2312..f02729cd2 100644
--- a/src/core/render_widget_host_view_qt.cpp
+++ b/src/core/render_widget_host_view_qt.cpp
@@ -694,7 +694,6 @@ void RenderWidgetHostViewQt::notifyResize()
 bool RenderWidgetHostViewQt::forwardEvent(QEvent *event)
 {
     switch (event->type()) {
-    case QEvent::MouseButtonDblClick:
     case QEvent::MouseButtonPress:
         Focus(); // Fall through.
     case QEvent::MouseButtonRelease:
@@ -869,12 +868,8 @@ bool RenderWidgetHostViewQt::IsPopup() const
 
 void RenderWidgetHostViewQt::handleMouseEvent(QMouseEvent* event)
 {
-    int eventType = event->type();
-    if (eventType == QEvent::MouseButtonDblClick)
-        return;
-
     blink::WebMouseEvent webEvent = WebEventFactory::toWebMouseEvent(event, dpiScale());
-    if (eventType == QMouseEvent::MouseButtonPress) {
+    if (event->type() == QMouseEvent::MouseButtonPress) {
         if (event->button() != m_clickHelper.lastPressButton
             || (event->timestamp() - m_clickHelper.lastPressTimestamp > static_cast<ulong>(qGuiApp->styleHints()->mouseDoubleClickInterval()))
             || (event->pos() - m_clickHelper.lastPressPosition).manhattanLength() > qGuiApp->styleHints()->startDragDistance())
diff --git a/src/webengine/render_widget_host_view_qt_delegate_quick.cpp b/src/webengine/render_widget_host_view_qt_delegate_quick.cpp
index 4dc9031ad..8d7f298e7 100644
--- a/src/webengine/render_widget_host_view_qt_delegate_quick.cpp
+++ b/src/webengine/render_widget_host_view_qt_delegate_quick.cpp
@@ -172,11 +172,6 @@ void RenderWidgetHostViewQtDelegateQuick::mouseReleaseEvent(QMouseEvent *event)
     m_client->forwardEvent(event);
 }
 
-void RenderWidgetHostViewQtDelegateQuick::mouseDoubleClickEvent(QMouseEvent *event)
-{
-    m_client->forwardEvent(event);
-}
-
 void RenderWidgetHostViewQtDelegateQuick::keyPressEvent(QKeyEvent *event)
 {
     m_client->forwardEvent(event);
diff --git a/src/webengine/render_widget_host_view_qt_delegate_quick.h b/src/webengine/render_widget_host_view_qt_delegate_quick.h
index 71a2de013..2efb2d098 100644
--- a/src/webengine/render_widget_host_view_qt_delegate_quick.h
+++ b/src/webengine/render_widget_host_view_qt_delegate_quick.h
@@ -74,7 +74,6 @@ protected:
     virtual void mousePressEvent(QMouseEvent *event) Q_DECL_OVERRIDE;
     virtual void mouseMoveEvent(QMouseEvent *event) Q_DECL_OVERRIDE;
     virtual void mouseReleaseEvent(QMouseEvent *event) Q_DECL_OVERRIDE;
-    virtual void mouseDoubleClickEvent(QMouseEvent *event) Q_DECL_OVERRIDE;
     virtual void keyPressEvent(QKeyEvent *event) Q_DECL_OVERRIDE;
     virtual void keyReleaseEvent(QKeyEvent *event) Q_DECL_OVERRIDE;
     virtual void wheelEvent(QWheelEvent *event) Q_DECL_OVERRIDE;
diff --git a/src/webenginewidgets/render_widget_host_view_qt_delegate_widget.cpp b/src/webenginewidgets/render_widget_host_view_qt_delegate_widget.cpp
index 6c3f1cb1c..46f531e52 100644
--- a/src/webenginewidgets/render_widget_host_view_qt_delegate_widget.cpp
+++ b/src/webenginewidgets/render_widget_host_view_qt_delegate_widget.cpp
@@ -178,7 +178,20 @@ void RenderWidgetHostViewQtDelegateWidget::resizeEvent(QResizeEvent *resizeEvent
 
 bool RenderWidgetHostViewQtDelegateWidget::event(QEvent *event)
 {
-    if (!m_client->forwardEvent(event))
+    bool handled = false;
+    if (event->type() == QEvent::MouseButtonDblClick) {
+        // QWidget keeps the Qt4 behavior where the DblClick event would replace the Press event.
+        // QtQuick is different by sending both the Press and DblClick events for the second press
+        // where we can simply ignore the DblClick event.
+        QMouseEvent *dblClick = static_cast<QMouseEvent *>(event);
+        QMouseEvent press(QEvent::MouseButtonPress, dblClick->localPos(), dblClick->windowPos(), dblClick->screenPos(),
+            dblClick->button(), dblClick->buttons(), dblClick->modifiers());
+        press.setTimestamp(dblClick->timestamp());
+        handled = m_client->forwardEvent(&press);
+    } else
+        handled = m_client->forwardEvent(event);
+
+    if (!handled)
         return QOpenGLWidget::event(event);
     return true;
 }