cc: Partial tile update for one-copy raster.

cc/playback/raster_source_helper.h

 // Copyright 2014 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 CC_PLAYBACK_RASTER_SOURCE_HELPER_H_
 #define CC_PLAYBACK_RASTER_SOURCE_HELPER_H_
 
 #include "cc/base/cc_export.h"
 #include "third_party/skia/include/core/SkColor.h"
 #include "ui/gfx/geometry/rect.h"
 
 class SkCanvas;
 
 namespace cc {
 
 class CC_EXPORT RasterSourceHelper {
  public:
   static void PrepareForPlaybackToCanvas(SkCanvas* canvas,
-                                         const gfx::Rect& canvas_rect,
+                                         const gfx::Rect& canvas_bitmap_rect,
+                                         const gfx::Rect& canvas_playback_rect,

[reveman, 2015/05/22 17:15:13]

nit: and here

                                          const gfx::Rect& source_rect,
                                          float contents_scale,
                                          SkColor background_color,
                                          bool clear_canvas_with_debug_color,
                                          bool requires_clear);
 };
 
 }  // namespace cc
 
 #endif  // CC_PLAYBACK_RASTER_SOURCE_HELPER_H_