Implement a Hit Test Cache.

public/platform/WebLayer.h

 /*
  * Copyright (C) 2011 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 213 matching lines @@
     virtual void setScrollClient(WebLayerScrollClient*) = 0;
 
     // Forces this layer to use a render surface. There is no benefit in doing
     // so, but this is to facilitate benchmarks and tests.
     virtual void setForceRenderSurface(bool) = 0;
 
     // True if the layer is not part of a tree attached to a WebLayerTreeView.
     virtual bool isOrphan() const = 0;
 
     virtual void setWebLayerClient(WebLayerClient*) = 0;
+
+    // TODO(dtapuska): Make pure virtual once cc side has landed crbug.com/398920.
+    virtual void setHitCacheRect(const WebRect&) { };

[esprehn, 2015/06/12 05:09:30]

I'd probably call this HitTestCache since that's also what the class is called.

[dtapuska, 2015/06/12 15:30:38]

Done.

 };
 
 } // namespace blink
 
 #endif // WebLayer_h