Issue repaints for RenderLayers that get new composited backings after

Source/core/rendering/compositing/CompositingLayerAssigner.h

 /*
  * Copyright (C) 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2014 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 22 matching lines @@
 
 namespace WebCore {
 
 class RenderLayer;
 
 class CompositingLayerAssigner {
 public:
     explicit CompositingLayerAssigner(RenderLayerCompositor*);
     ~CompositingLayerAssigner();
 
-    void assign(RenderLayer* updateRoot, bool& layersChanged);
+    void assign(RenderLayer* updateRoot, bool& layersChanged, Vector<RenderLayer*>& layersNeedingRepaint);

[abarth-chromium, 2014/06/06 03:22:21]

You can also store this sort of variable on the CompositingLayerAssigner
instance.  That way you don't need to pass it around through the entire
recursion.

 
     // FIXME: This function should be private. We should remove the one caller
     // once we've fixed the compositing chicken/egg issues.
     CompositingStateTransitionType computeCompositedLayerUpdate(RenderLayer*);
 
 private:
     struct SquashingState {
         SquashingState()
             : mostRecentMapping(0)
             , hasMostRecentMapping(false)
@@ skipping 16 matching lines @@
         size_t nextSquashedLayerIndex;
 
         // The absolute bounding rect of all the squashed layers.
         IntRect boundingRect;
 
         // This is simply the sum of the areas of the squashed rects. This can be very skewed if the rects overlap,
         // but should be close enough to drive a heuristic.
         uint64_t totalAreaOfSquashedRects;
     };
 
-    void assignLayersToBackingsInternal(RenderLayer*, SquashingState&, bool& layersChanged);
-    void assignLayersToBackingsForReflectionLayer(RenderLayer* reflectionLayer, bool& layersChanged);
+    void assignLayersToBackingsInternal(RenderLayer*, SquashingState&, bool& layersChanged, Vector<RenderLayer*>& layersNeedingRepaint);
+    void assignLayersToBackingsForReflectionLayer(RenderLayer* reflectionLayer, bool& layersChanged, Vector<RenderLayer*>& layersNeedingRepaint);
     bool canSquashIntoCurrentSquashingOwner(const RenderLayer*, const SquashingState&);
     bool squashingWouldExceedSparsityTolerance(const RenderLayer* candidate, const SquashingState&);
-    bool updateSquashingAssignment(RenderLayer*, SquashingState&, CompositingStateTransitionType);
+    bool updateSquashingAssignment(RenderLayer*, SquashingState&, CompositingStateTransitionType, Vector<RenderLayer*>& layersNeedingRepaint);
     bool needsOwnBacking(const RenderLayer*) const;
 
     RenderLayerCompositor* m_compositor;
     bool m_layerSquashingEnabled;
 };
 
 } // namespace WebCore
 
 #endif // CompositingLayerAssigner_h