Introduce painted-device-scale-factor and use it when --enable-use-zoom-for-dsf is specified.

cc/trees/layer_tree_host.h

 // Copyright 2011 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.
 
 #ifndef CC_TREES_LAYER_TREE_HOST_H_
 #define CC_TREES_LAYER_TREE_HOST_H_
 
 #include <limits>
 #include <set>
 #include <string>
@@ skipping 220 matching lines @@
 
   void StartPageScaleAnimation(const gfx::Vector2d& target_offset,
                                bool use_anchor,
                                float scale,
                                base::TimeDelta duration);
 
   void ApplyScrollAndScale(ScrollAndScaleSet* info);
   void SetImplTransform(const gfx::Transform& transform);
 
   void SetDeviceScaleFactor(float device_scale_factor);
+  void SetPaintedDeviceScaleFactor(float painted_device_scale_factor);
+
   float device_scale_factor() const { return device_scale_factor_; }
 
   void UpdateTopControlsState(TopControlsState constraints,
                               TopControlsState current,
                               bool animate);
 
   HeadsUpDisplayLayer* hud_layer() const { return hud_layer_.get(); }
 
   Proxy* proxy() const { return proxy_.get(); }
   AnimationRegistrar* animation_registrar() const {
@@ skipping 185 matching lines @@
   base::WeakPtr<InputHandler> input_handler_weak_ptr_;
 
   const LayerTreeSettings settings_;
   LayerTreeDebugState debug_state_;
 
   gfx::Size device_viewport_size_;
   bool top_controls_shrink_blink_size_;
   float top_controls_height_;
   float top_controls_shown_ratio_;
   float device_scale_factor_;
+  float painted_device_scale_factor_;
 
   bool visible_;
 
   float page_scale_factor_;
   float min_page_scale_factor_;
   float max_page_scale_factor_;
   gfx::Vector2dF elastic_overscroll_;
   bool has_gpu_rasterization_trigger_;
   bool content_is_suitable_for_gpu_rasterization_;
   bool gpu_rasterization_histogram_recorded_;
@@ skipping 36 matching lines @@
 
   uint32_t surface_id_namespace_;
   uint32_t next_surface_sequence_;
 
   DISALLOW_COPY_AND_ASSIGN(LayerTreeHost);
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_LAYER_TREE_HOST_H_