Turn off computation of the interest rect in cc in synchronized paint mode.

cc/playback/display_list_recording_source.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_DISPLAY_LIST_RECORDING_SOURCE_H_
 #define CC_PLAYBACK_DISPLAY_LIST_RECORDING_SOURCE_H_
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "cc/base/cc_export.h"
@@ skipping 34 matching lines @@
   void SetSlowdownRasterScaleFactor(int factor);
   void SetGenerateDiscardableImagesMetadata(bool generate_metadata);
   void SetBackgroundColor(SkColor background_color);
   void SetRequiresClear(bool requires_clear);
 
   // These functions are virtual for testing.
   virtual scoped_refptr<DisplayListRasterSource> CreateRasterSource(
       bool can_use_lcd_text) const;
   virtual bool IsSuitableForGpuRasterization() const;
 
-  // Returns true if the new recorded viewport exposes enough new area to be
-  // worth re-recording.
-  static bool ExposesEnoughNewArea(
-      const gfx::Rect& current_recorded_viewport,
-      const gfx::Rect& potential_new_recorded_viewport,
-      const gfx::Size& layer_size);
-
   gfx::Rect recorded_viewport() const { return recorded_viewport_; }
 
  protected:
   void Clear();
 
   gfx::Rect recorded_viewport_;
   gfx::Size size_;
   int slow_down_raster_scale_factor_for_debug_;
   bool generate_discardable_images_metadata_;
   bool requires_clear_;
   bool is_solid_color_;
   bool clear_canvas_with_debug_color_;
   SkColor solid_color_;
   SkColor background_color_;
-  int pixel_record_distance_;
 
   scoped_refptr<DisplayItemList> display_list_;
   size_t painter_reported_memory_usage_;
 
  private:
+  void UpdateInvalidationForNewViewport(const gfx::Rect& old_recorded_viewport,
+                                        const gfx::Rect& new_recorded_viewport,
+                                        Region* invalidation);
+
   friend class DisplayListRasterSource;
 
   void DetermineIfSolidColor();
 
   DISALLOW_COPY_AND_ASSIGN(DisplayListRecordingSource);
 };
 
 }  // namespace cc
 
 #endif  // CC_PLAYBACK_DISPLAY_LIST_RECORDING_SOURCE_H_