Add fixed raster scale use counter histograms.

cc/layers/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/layer_impl.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 66 matching lines @@
       transform_tree_index_(-1),
       effect_tree_index_(-1),
       clip_tree_index_(-1),
       scroll_tree_index_(-1),
       sorting_context_id_(0),
       current_draw_mode_(DRAW_MODE_NONE),
       element_id_(0),
       mutable_properties_(MutableProperty::kNone),
       debug_info_(nullptr),
       scrolls_drawn_descendant_(false),
-      layer_or_descendant_has_touch_handler_(false) {
+      layer_or_descendant_has_touch_handler_(false),
+      has_will_change_transform_hint_(false) {
   DCHECK_GT(layer_id_, 0);
 
   DCHECK(layer_tree_impl_);
   layer_tree_impl_->RegisterLayer(this);
   layer_tree_impl_->AddToElementMap(this);
 
   SetNeedsPushProperties();
 }
 
 LayerImpl::~LayerImpl() {
@@ skipping 42 matching lines @@
     layer_tree_impl_->RemoveLayer(child->id());
   children_.clear();
 }
 
 void LayerImpl::ClearLinksToOtherLayers() {
   children_.clear();
   mask_layer_ = nullptr;
   replica_layer_ = nullptr;
 }
 
+void LayerImpl::SetHasWillChangeTransformHint(bool has_will_change) {
+  if (has_will_change_transform_hint_ == has_will_change)
+    return;
+  has_will_change_transform_hint_ = has_will_change;
+  SetNeedsPushProperties();
+}
+
 void LayerImpl::SetDebugInfo(
     std::unique_ptr<base::trace_event::ConvertableToTraceFormat> debug_info) {
   owned_debug_info_ = std::move(debug_info);
   debug_info_ = owned_debug_info_.get();
   SetNeedsPushProperties();
 }
 
 void LayerImpl::DistributeScroll(ScrollState* scroll_state) {
   DCHECK(scroll_state);
   if (scroll_state->FullyConsumed())
@@ skipping 328 matching lines @@
   // 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_);
 
   if (owned_debug_info_)
     layer->SetDebugInfo(std::move(owned_debug_info_));
 
+  layer->SetHasWillChangeTransformHint(has_will_change_transform_hint());
+
   // Reset any state that should be cleared for the next update.
   layer_property_changed_ = false;
   update_rect_ = gfx::Rect();
   layer_tree_impl()->RemoveLayerShouldPushProperties(this);
 }
 
 bool LayerImpl::IsAffectedByPageScale() const {
   TransformTree& transform_tree =
       layer_tree_impl()->property_trees()->transform_tree;
   return transform_tree.Node(transform_tree_index())
@@ skipping 755 matching lines @@
     replica_layer_->AsValueInto(state);
     state->EndDictionary();
   }
 
   state->SetBoolean("can_use_lcd_text", can_use_lcd_text());
   state->SetBoolean("contents_opaque", contents_opaque());
 
   state->SetBoolean("has_animation_bounds",
                     layer_tree_impl_->HasAnimationThatInflatesBounds(this));
 
+  state->SetBoolean("has_will_change_transform_hint",
+                    has_will_change_transform_hint());
+
   gfx::BoxF box;
   if (LayerUtils::GetAnimationBounds(*this, &box))
     MathUtil::AddToTracedValue("animation_bounds", box, state);
 
   if (debug_info_) {
     std::string str;
     debug_info_->AppendAsTraceFormat(&str);
     base::JSONReader json_reader;
     std::unique_ptr<base::Value> debug_info_value(json_reader.ReadToValue(str));
 
@@ skipping 127 matching lines @@
            .layer_transforms_should_scale_layer_contents) {
     return default_scale;
   }
 
   gfx::Vector2dF transform_scales = MathUtil::ComputeTransform2dScaleComponents(
       DrawTransform(), default_scale);
   return std::max(transform_scales.x(), transform_scales.y());
 }
 
 }  // namespace cc