Migrate Graphics2D to new design.

ppapi/proxy/ppb_image_data_proxy.h

Index: ppapi/proxy/ppb_image_data_proxy.h
diff --git a/ppapi/proxy/ppb_image_data_proxy.h b/ppapi/proxy/ppb_image_data_proxy.h
index 6ddbafa33921190b88076026dd90ed327f458399..c56217a5f4674c8d4f2afe921232ffa995a98909 100644
--- a/ppapi/proxy/ppb_image_data_proxy.h
+++ b/ppapi/proxy/ppb_image_data_proxy.h
@@ -59,11 +59,10 @@ class ImageData : public ppapi::Resource,
   virtual int32_t GetSharedMemory(int* handle, uint32_t* byte_count) OVERRIDE;
   virtual SkCanvas* GetPlatformCanvas() OVERRIDE;
   virtual SkCanvas* GetCanvas() OVERRIDE;
+  virtual void SetUsedInReplaceContents() OVERRIDE;
 
   const PP_ImageDataDesc& desc() const { return desc_; }
 
-  void set_used_in_replace_contents() { used_in_replace_contents_ = true; }
-
   // Prepares this image data to be recycled to the plugin. The contents will be
   // cleared if zero_contents is set.
   void RecycleToPlugin(bool zero_contents);