When possible, draw the toolbar shadow with the compositor

chrome/browser/android/compositor/layer/tab_layer.h

 // Copyright 2014 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 CHROME_BROWSER_ANDROID_COMPOSITOR_LAYER_TAB_LAYER_H_
 #define CHROME_BROWSER_ANDROID_COMPOSITOR_LAYER_TAB_LAYER_H_
 
 #include <memory>
 
 #include "base/macros.h"
@@ skipping 31 matching lines @@
 class TabLayer : public Layer {
  public:
   static scoped_refptr<TabLayer> Create(bool incognito,
                                         ui::ResourceManager* resource_manager,
                                         LayerTitleCache* layer_title_cache,
                                         TabContentManager* tab_content_manager);
 
   void SetProperties(int id,
                      bool can_use_live_layer,
                      int toolbar_resource_id,
+                     int toolbar_shadow_resource_id,
                      int close_button_resource_id,
                      int shadow_resource_id,
                      int contour_resource_id,
                      int back_logo_resource_id,
                      int border_resource_id,
                      int border_inner_shadow_resource_id,
                      int default_background_color,
                      int back_logo_color,
                      bool is_portrait,
                      float x,
@@ skipping 28 matching lines @@
                      int toolbar_background_color,
                      int close_button_color,
                      bool anonymize_toolbar,
                      int toolbar_textbox_resource_id,
                      int toolbar_textbox_background_color,
                      float toolbar_textbox_alpha,
                      float toolbar_alpha,
                      float toolbar_y_offset,
                      float side_border_scale,
                      bool attach_content,
-                     bool inset_border);
+                     bool inset_border,
+                     bool needs_toolbar_shadow);
 
   bool is_incognito() const { return incognito_; }
 
   scoped_refptr<cc::Layer> layer() override;
 
   static void ComputePaddingPositions(const gfx::Size& content_size,
                                       const gfx::Size& desired_size,
                                       gfx::Rect* side_padding_rect,
                                       gfx::Rect* bottom_padding_rect);
 
@@ skipping 40 matching lines @@
   scoped_refptr<cc::UIResourceLayer> back_logo_;
   float brightness_;
 
   DISALLOW_COPY_AND_ASSIGN(TabLayer);
 };
 
 }  //  namespace android
 }  //  namespace chrome
 
 #endif  // CHROME_BROWSER_ANDROID_COMPOSITOR_LAYER_TAB_LAYER_H_