cc: Remove all remaining use of WebCore Rect/Point/Size types from the compositor.

cc/thread_proxy.h

Index: cc/thread_proxy.h
diff --git a/cc/thread_proxy.h b/cc/thread_proxy.h
index 1a24ec5578511ab2969fbeae6f7629f1ec8dd980..7e14347019537b62fae27b350ed4de1ed688b086 100644
--- a/cc/thread_proxy.h
+++ b/cc/thread_proxy.h
@@ -30,7 +30,7 @@ public:
 
     // Proxy implementation
     virtual bool compositeAndReadback(void *pixels, const gfx::Rect&) OVERRIDE;
-    virtual void startPageScaleAnimation(const IntSize& targetPosition, bool useAnchor, float scale, base::TimeDelta duration) OVERRIDE;
+    virtual void startPageScaleAnimation(gfx::Vector2d targetOffset, bool useAnchor, float scale, base::TimeDelta duration) OVERRIDE;
     virtual void finishAllRendering() OVERRIDE;
     virtual bool isStarted() const OVERRIDE;
     virtual bool initializeContext() OVERRIDE;
@@ -111,7 +111,7 @@ private:
     void beginFrameCompleteOnImplThread(CompletionEvent*, ResourceUpdateQueue*);
     void beginFrameAbortedOnImplThread();
     void requestReadbackOnImplThread(ReadbackRequest*);
-    void requestStartPageScaleAnimationOnImplThread(IntSize targetPosition, bool useAnchor, float scale, base::TimeDelta duration);
+    void requestStartPageScaleAnimationOnImplThread(gfx::Vector2d targetOffset, bool useAnchor, float scale, base::TimeDelta duration);
     void finishAllRenderingOnImplThread(CompletionEvent*);
     void initializeImplOnImplThread(CompletionEvent*, InputHandler*);
     void setSurfaceReadyOnImplThread();