Migrate Graphics2D to new design.

ppapi/thunk/ppb_graphics_2d_api.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#ifndef PPAPI_THUNK_PPB_GRAPHICS_2D_API_H_
+#define PPAPI_THUNK_PPB_GRAPHICS_2D_API_H_
+
 #include "base/memory/ref_counted.h"
 #include "ppapi/c/pp_bool.h"
 #include "ppapi/c/pp_completion_callback.h"
 #include "ppapi/c/pp_point.h"
 #include "ppapi/c/pp_rect.h"
 #include "ppapi/c/pp_resource.h"
 #include "ppapi/c/pp_size.h"
 
 namespace ppapi {
 
@@ skipping 19 matching lines @@
   // contents (which leaves the "old" ImageData unowned), the resource ID of
   // the old image data will be placed into |*old_image_data| synchronously
   // (not when the flush callback completes).
   //
   // When this happens, a reference to this resource will be transferred to the
   // caller. If there is no replace contents operation, old_image_data will be
   // ignored. If |*old_image_data| is null, then the old image data will be
   // destroyed if there was one.
   virtual int32_t Flush(scoped_refptr<TrackedCallback> callback,
                         PP_Resource* old_image_data) = 0;
+
+  // Test only
+  virtual bool ReadImageData(PP_Resource image, const PP_Point* top_left) = 0;
 };
 
 }  // namespace thunk
 }  // namespace ppapi
+
+#endif  // PPAPI_THUNK_PPB_GRAPHICS_2D_API_H_