Revert 261000 "Re-raster GPU-rasterized layers during scale animations"

cc/layers/picture_layer_impl.cc

 // 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.
 
 #include "cc/layers/picture_layer_impl.h"
 
 #include <algorithm>
 #include <limits>
 
 #include "base/time/time.h"
@@ skipping 1016 matching lines @@
   high_res->set_resolution(HIGH_RESOLUTION);
 
   SanityCheckTilingState();
 }
 
 bool PictureLayerImpl::ShouldAdjustRasterScale(
     bool animating_transform_to_screen) const {
   if (was_animating_transform_to_screen_ != animating_transform_to_screen)
     return true;
 
-  if (animating_transform_to_screen &&
-      raster_contents_scale_ != ideal_contents_scale_ &&
-      use_gpu_rasterization())
-    return true;
-
   bool is_pinching = layer_tree_impl()->PinchGestureActive();
   if (is_pinching && raster_page_scale_) {
     // We change our raster scale when it is:
     // - Higher than ideal (need a lower-res tiling available)
     // - Too far from ideal (need a higher-res tiling available)
     float ratio = ideal_page_scale_ / raster_page_scale_;
     if (raster_page_scale_ > ideal_page_scale_ ||
         ratio > kMaxScaleRatioDuringPinch)
       return true;
   }
@@ skipping 74 matching lines @@
         zooming_out ? old_raster_contents_scale / kMaxScaleRatioDuringPinch
                     : old_raster_contents_scale * kMaxScaleRatioDuringPinch;
     raster_contents_scale_ = SnappedContentsScale(desired_contents_scale);
     raster_page_scale_ =
         raster_contents_scale_ / raster_device_scale_ / raster_source_scale_;
   }
 
   raster_contents_scale_ =
       std::max(raster_contents_scale_, MinimumContentsScale());
 
-  // If we're not re-rasterizing during animation, rasterize at the maximum
+  // Since we're not re-rasterizing during animation, rasterize at the maximum
   // scale that will occur during the animation, if the maximum scale is
   // known.
-  if (animating_transform_to_screen && !use_gpu_rasterization()) {
+  if (animating_transform_to_screen) {
     if (maximum_animation_contents_scale > 0.f) {
       raster_contents_scale_ =
           std::max(raster_contents_scale_, maximum_animation_contents_scale);
     } else {
       raster_contents_scale_ =
           std::max(raster_contents_scale_,
                    1.f * ideal_page_scale_ * ideal_device_scale_);
     }
   }
 
@@ skipping 412 matching lines @@
   return iterator_index_ < iterators_.size();
 }
 
 bool PictureLayerImpl::LayerEvictionTileIterator::IsCorrectType(
     PictureLayerTiling::TilingEvictionTileIterator* it) const {
   return it->get_type() == iteration_stage_ &&
          (**it)->required_for_activation() == required_for_activation_;
 }
 
 }  // namespace cc