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

cc/layers/picture_image_layer_impl.cc

 // Copyright 2013 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.
 
 #include "cc/layers/picture_image_layer_impl.h"
 
 #include <algorithm>
 
 #include "cc/debug/debug_colors.h"
 #include "cc/trees/layer_tree_impl.h"
@@ skipping 13 matching lines @@
 
 scoped_ptr<LayerImpl> PictureImageLayerImpl::CreateLayerImpl(
     LayerTreeImpl* tree_impl) {
   return PictureImageLayerImpl::Create(tree_impl, id()).PassAs<LayerImpl>();
 }
 
 void PictureImageLayerImpl::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) {
   // CalculateRasterContentsScale always returns 1.f, so make that the ideal
   // scale.
   ideal_contents_scale = 1.f;
   PictureLayerImpl::CalculateContentsScale(ideal_contents_scale,
                                            device_scale_factor,
                                            page_scale_factor,
+                                           maximum_animation_scale_factor,
                                            animating_transform_to_screen,
                                            contents_scale_x,
                                            contents_scale_y,
                                            content_bounds);
 }
 
 void PictureImageLayerImpl::GetDebugBorderProperties(
     SkColor* color, float* width) const {
   *color = DebugColors::ImageLayerBorderColor();
   *width = DebugColors::ImageLayerBorderWidth(layer_tree_impl());
 }
 
 bool PictureImageLayerImpl::ShouldAdjustRasterScale(
     bool animating_transform_to_screen) const {
   return false;
 }
 
 void PictureImageLayerImpl::RecalculateRasterScales(
-    bool animating_transform_to_screen) {
+    bool animating_transform_to_screen,
+    float maximum_animation_scale_factor) {
   // Defaults from PictureLayerImpl.
-  PictureLayerImpl::RecalculateRasterScales(animating_transform_to_screen);
+  PictureLayerImpl::RecalculateRasterScales(animating_transform_to_screen,
+                                            maximum_animation_scale_factor);
 
   // Don't scale images during rastering to ensure image quality, save memory
   // and avoid frequent re-rastering on change of scale.
   raster_contents_scale_ = std::max(1.f, MinimumContentsScale());
   // We don't need low res tiles.
   low_res_raster_contents_scale_ = raster_contents_scale_;
 }
 
 }  // namespace cc