Plumb preferred raster scale for background images from Blink to cc layers.

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 49 matching lines @@
       scroll_clip_layer_id(INVALID_ID),
       user_scrollable_horizontal(true),
       user_scrollable_vertical(true),
       main_thread_scrolling_reasons(
           MainThreadScrollingReason::kNotScrollingOnMain),
       is_container_for_fixed_position_layers(false),
       mutable_properties(MutableProperty::kNone),
       scroll_parent(nullptr),
       clip_parent(nullptr),
       has_will_change_transform_hint(false),
+      has_preferred_raster_scale(false),
       hide_layer_and_subtree(false),
-      client(nullptr) {}
+      client(nullptr),
+      preferred_raster_scale(1.0) {}
 
 Layer::Inputs::~Inputs() {}
 
 scoped_refptr<Layer> Layer::Create() {
   return make_scoped_refptr(new Layer());
 }
 
 Layer::Layer()
     : ignore_set_needs_commit_(false),
       parent_(nullptr),
@@ skipping 1093 matching lines @@
         ->scroll_tree.SetScrollOffsetClobberActiveValue(layer->id());
 
   // 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.
   inputs_.update_rect.Union(layer->update_rect());
   layer->SetUpdateRect(inputs_.update_rect);
 
   layer->SetHasWillChangeTransformHint(has_will_change_transform_hint());
+  if (has_preferred_raster_scale())
+    layer->SetPreferredRasterScale(preferred_raster_scale());
+  else
+    layer->ClearPreferredRasterScale();
   layer->SetNeedsPushProperties();
 
   // Reset any state that should be cleared for the next update.
   subtree_property_changed_ = false;
   inputs_.update_rect = gfx::Rect();
 
   layer_tree_->RemoveLayerShouldPushProperties(this);
 }
 
 void Layer::TakeCopyRequests(
@@ skipping 558 matching lines @@
              : false;
 }
 
 void Layer::SetHasWillChangeTransformHint(bool has_will_change) {
   if (inputs_.has_will_change_transform_hint == has_will_change)
     return;
   inputs_.has_will_change_transform_hint = has_will_change;
   SetNeedsCommit();
 }
 
+void Layer::SetPreferredRasterScale(float preferred_raster_scale) {
+  if (inputs_.has_preferred_raster_scale &&
+      inputs_.preferred_raster_scale == preferred_raster_scale)
+    return;
+
+  inputs_.has_preferred_raster_scale = true;
+  inputs_.preferred_raster_scale = preferred_raster_scale;
+  SetNeedsCommit();
+}
+
+void Layer::ClearPreferredRasterScale() {
+  if (!inputs_.has_preferred_raster_scale)
+    return;
+  inputs_.has_preferred_raster_scale = false;
+  inputs_.preferred_raster_scale = 1.0f;
+  SetNeedsCommit();
+}
+
 AnimationHost* Layer::GetAnimationHost() const {
   return layer_tree_ ? layer_tree_->animation_host() : nullptr;
 }
 
 ElementListType Layer::GetElementTypeForAnimation() const {
   return ElementListType::ACTIVE;
 }
 
 ScrollbarLayerInterface* Layer::ToScrollbarLayer() {
   return nullptr;
@@ skipping 89 matching lines @@
 
 LayerTree* Layer::GetLayerTree() const {
   return layer_tree_;
 }
 
 void Layer::SetLayerIdForTesting(int id) {
   inputs_.layer_id = id;
 }
 
 }  // namespace cc