Optimize repaint on FrameView resize

Source/core/rendering/RenderObject.h

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  *           (C) 2000 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Google 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
@@ skipping 593 matching lines @@
     // Returns the object containing this one. Can be different from parent for positioned elements.
     // If repaintContainer and repaintContainerSkipped are not null, on return *repaintContainerSkipped
     // is true if the renderer returned is an ancestor of repaintContainer.
     RenderObject* container(const RenderLayerModelObject* repaintContainer = 0, bool* repaintContainerSkipped = 0) const;
 
     virtual RenderObject* hoverAncestor() const { return parent(); }
 
     Element* offsetParent() const;
 
     void markContainingBlocksForLayout(bool scheduleRelayout = true, RenderObject* newRoot = 0, SubtreeLayoutScope* = 0);
-    void setNeedsLayout(MarkingBehavior = MarkContainingBlockChain, SubtreeLayoutScope* = 0);
+    void setNeedsLayout(MarkingBehavior = MarkContainingBlockChain, SubtreeLayoutScope* = 0, bool fullRepaintLayer = true);

[ojan, 2014/03/28 01:51:36]

We typically don't do booleans like this. This should be an enum instead. That
way it's clear in the calling code what this value represents.

[Xianzhu, 2014/03/28 16:26:01]

Done.

     void clearNeedsLayout();
     void setChildNeedsLayout(MarkingBehavior = MarkContainingBlockChain, SubtreeLayoutScope* = 0);
     void setNeedsPositionedMovementLayout();
     void setNeedsSimplifiedNormalFlowLayout();
     void setPreferredLogicalWidthsDirty(MarkingBehavior = MarkContainingBlockChain);
     void clearPreferredLogicalWidthsDirty();
     void invalidateContainerPreferredLogicalWidths();
 
     void setNeedsLayoutAndPrefWidthsRecalc()
     {
@@ skipping 637 matching lines @@
     if (isText() && !isBR())
         return false;
     return true;
 }
 
 inline bool RenderObject::isBeforeOrAfterContent() const
 {
     return isBeforeContent() || isAfterContent();
 }
 
-inline void RenderObject::setNeedsLayout(MarkingBehavior markParents, SubtreeLayoutScope* layouter)
+inline void RenderObject::setNeedsLayout(MarkingBehavior markParents, SubtreeLayoutScope* layouter, bool fullRepaintLayer)
 {
     ASSERT(!isSetNeedsLayoutForbidden());
     bool alreadyNeededLayout = m_bitfields.selfNeedsLayout();
     setSelfNeedsLayout(true);
     if (!alreadyNeededLayout) {
         if (markParents == MarkContainingBlockChain && (!layouter || layouter->root() != this))
             markContainingBlocksForLayout(true, 0, layouter);
-        if (hasLayer())
+        if (fullRepaintLayer && hasLayer())
             setLayerNeedsFullRepaint();

[ojan, 2014/03/28 01:51:36]

Really this code is wrong. I think we should probably have a FIXME to make this
code go away entirely, or at least to make fullRepaintLayer default to false.

[Xianzhu, 2014/03/28 16:26:01]

Done.

trchen@ is working on separating repaint and layout requirements in
StyleDifference. After that, perhaps we can remove the new parameter and the
above statement.

     }
 }
 
 inline void RenderObject::clearNeedsLayout()
 {
     setSelfNeedsLayout(false);
     setEverHadLayout(true);
     setPosChildNeedsLayout(false);
     setNeedsSimplifiedNormalFlowLayout(false);
     setNormalChildNeedsLayout(false);
@@ skipping 134 matching lines @@
 void showTree(const WebCore::RenderObject*);
 void showLineTree(const WebCore::RenderObject*);
 void showRenderTree(const WebCore::RenderObject* object1);
 // We don't make object2 an optional parameter so that showRenderTree
 // can be called from gdb easily.
 void showRenderTree(const WebCore::RenderObject* object1, const WebCore::RenderObject* object2);
 
 #endif
 
 #endif // RenderObject_h