Rasterize at maximum scale for scale animations on CPU-rasterized layers

cc/layers/contents_scaling_layer.h

 // Copyright 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 CC_LAYERS_CONTENTS_SCALING_LAYER_H_
 #define CC_LAYERS_CONTENTS_SCALING_LAYER_H_
 
 #include "cc/base/cc_export.h"
 #include "cc/layers/layer.h"
 
 namespace cc {
 
 // Base class for layers that need contents scale.
 // The content bounds are determined by bounds and scale of the contents.
 class CC_EXPORT ContentsScalingLayer : public Layer {
  public:
-  virtual void CalculateContentsScale(
-      float ideal_contents_scale,
-      float device_scale_factor,
-      float page_scale_factor,
-      bool animating_transform_to_screen,
-      float* contents_scale_x,
-      float* contents_scale_y,
-      gfx::Size* content_bounds) OVERRIDE;
+  virtual void CalculateContentsScale(float ideal_contents_scale,
+                                      float device_scale_factor,
+                                      float page_scale_factor,
+                                      float maximum_animation_scale_factor,
+                                      bool animating_transform_to_screen,
+                                      float* contents_scale_x,
+                                      float* contents_scale_y,
+                                      gfx::Size* content_bounds) OVERRIDE;
 
   virtual bool Update(ResourceUpdateQueue* queue,
                       const OcclusionTracker<Layer>* occlusion) OVERRIDE;
 
  protected:
   ContentsScalingLayer();
   virtual ~ContentsScalingLayer();
 
   gfx::Size ComputeContentBoundsForScale(float scale_x, float scale_y) const;
 
  private:
   float last_update_contents_scale_x_;
   float last_update_contents_scale_y_;
 
   DISALLOW_COPY_AND_ASSIGN(ContentsScalingLayer);
 };
 
 }  // namespace cc
 
 #endif  // CC_LAYERS_CONTENTS_SCALING_LAYER_H__