Add fixed raster scale use counter histograms.

cc/layers/layer.cc

 // Copyright 2010 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/layer.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 71 matching lines @@
       subtree_property_changed_(false),
       background_color_(0),
       safe_opaque_background_color_(0),
       opacity_(1.f),
       blend_mode_(SkXfermode::kSrcOver_Mode),
       draw_blend_mode_(SkXfermode::kSrcOver_Mode),
       scroll_parent_(nullptr),
       clip_parent_(nullptr),
       replica_layer_(nullptr),
       client_(nullptr),
-      num_unclipped_descendants_(0) {}
+      num_unclipped_descendants_(0),
+      has_will_change_transform_hint_(false) {}
 
 Layer::~Layer() {
   // Our parent should be holding a reference to us so there should be no
   // way for us to be destroyed while we still have a parent.
   DCHECK(!parent());
   // Similarly we shouldn't have a layer tree host since it also keeps a
   // reference to us.
   DCHECK(!layer_tree_host());
 
   RemoveFromScrollTree();
@@ skipping 1100 matching lines @@
     layer->PassCopyRequests(&main_thread_copy_requests);
   }
 
   // If the main thread commits multiple times before the impl thread actually
   // draws, then damage tracking will become incorrect if we simply clobber the
   // update_rect here. The LayerImpl's update_rect needs to accumulate (i.e.
   // union) any update changes that have occurred on the main thread.
   update_rect_.Union(layer->update_rect());
   layer->SetUpdateRect(update_rect_);
 
+  layer->set_has_will_change_transform_hint(has_will_change_transform_hint());
+
   // Reset any state that should be cleared for the next update.
   subtree_property_changed_ = false;
   update_rect_ = gfx::Rect();
 
   layer_tree_host()->RemoveLayerShouldPushProperties(this);
 }
 
 void Layer::SetTypeForProtoSerialization(proto::LayerNode* proto) const {
   proto->set_type(proto::LayerNode::LAYER);
 }
@@ skipping 530 matching lines @@
       ->data.num_copy_requests_in_subtree;
 }
 
 gfx::Transform Layer::screen_space_transform() const {
   DCHECK_NE(transform_tree_index_, -1);
   return draw_property_utils::ScreenSpaceTransform(
       this, layer_tree_host_->property_trees()->transform_tree);
 }
 
 }  // namespace cc