Raster display item lists via a visual rect RTree.

third_party/WebKit/Source/platform/graphics/paint/PaintArtifact.h

Index: third_party/WebKit/Source/platform/graphics/paint/PaintArtifact.h
diff --git a/third_party/WebKit/Source/platform/graphics/paint/PaintArtifact.h b/third_party/WebKit/Source/platform/graphics/paint/PaintArtifact.h
index 7607cbad087fbdc7f434565389169020560647e2..85a528853e3ccfb182bcfac12f0c1063f432b983 100644
--- a/third_party/WebKit/Source/platform/graphics/paint/PaintArtifact.h
+++ b/third_party/WebKit/Source/platform/graphics/paint/PaintArtifact.h
@@ -30,6 +30,8 @@ public:
     PaintArtifact();
     ~PaintArtifact();
 
+    typedef WTF::HashMap<DisplayItemClient, IntRect> DisplayItemRectMap;
+
     bool isEmpty() const { return m_displayItemList.isEmpty(); }
 
     DisplayItemList& displayItemList() { return m_displayItemList; }
@@ -49,7 +51,7 @@ public:
     void replay(GraphicsContext&) const;
 
     // Writes the paint artifact into a WebDisplayItemList.
-    void appendToWebDisplayItemList(WebDisplayItemList*) const;
+    void appendToWebDisplayItemList(const DisplayItemRectMap& itemRects, WebDisplayItemList*) const;
 
 private:
     DisplayItemList m_displayItemList;