Implement transform/clip support for Android WebView.

cc/output/output_surface.h

Index: cc/output/output_surface.h
diff --git a/cc/output/output_surface.h b/cc/output/output_surface.h
index d6f4b82ed8b64d9a9d81a87d52a5b0552746c852..00877de68c8f8baa72c8113f87982225b8be2fa2 100644
--- a/cc/output/output_surface.h
+++ b/cc/output/output_surface.h
@@ -89,6 +89,7 @@ class CC_EXPORT OutputSurface {
   virtual void DiscardBackbuffer();
 
   virtual void Reshape(gfx::Size size, float scale_factor);
+  virtual gfx::Size SurfaceSize() const;
 
   virtual void BindFramebuffer();
 
@@ -110,6 +111,8 @@ class CC_EXPORT OutputSurface {
   scoped_ptr<WebKit::WebGraphicsContext3D> context3d_;
   scoped_ptr<cc::SoftwareOutputDevice> software_device_;
   bool has_gl_discard_backbuffer_;
+  gfx::Size surface_size_;
+  float device_scale_factor_;
 
   scoped_ptr<OutputSurfaceCallbacks> callbacks_;