Combine ViewHostMsg_{Paint,Scroll}Rect into one IPC....

chrome/browser/renderer_host/test/test_render_view_host.h

Index: chrome/browser/renderer_host/test/test_render_view_host.h
===================================================================
--- chrome/browser/renderer_host/test/test_render_view_host.h	(revision 34937)
+++ chrome/browser/renderer_host/test/test_render_view_host.h	(working copy)
@@ -64,8 +64,10 @@
   virtual void UpdateCursor(const WebCursor& cursor) {}
   virtual void UpdateCursorIfOverSelf() {}
   virtual void IMEUpdateStatus(int control, const gfx::Rect& caret_rect) {}
-  virtual void DidPaintRect(const gfx::Rect& rect) {}
-  virtual void DidScrollRect(const gfx::Rect& rect, int dx, int dy) {}
+  virtual void DidPaintBackingStoreRects(
+      const std::vector<gfx::Rect>& rects) {}
+  virtual void DidScrollBackingStoreRect(
+      const gfx::Rect& rect, int dx, int dy) {}
   virtual void RenderViewGone() { delete this; }
   virtual void WillDestroyRenderWidget(RenderWidgetHost* rwh) { }
   virtual void Destroy() {}