Introduce bottom controls to CC and let it respond to scrolling

content/browser/renderer_host/render_widget_host_view_base.h

 // Copyright (c) 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.
 
 #ifndef CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_BASE_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_BASE_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 142 matching lines @@
   // The size of the view's backing surface in non-DPI-adjusted pixels.
   virtual gfx::Size GetPhysicalBackingSize() const;
 
   // Whether or not Blink's viewport size should be shrunk by the height of the
   // URL-bar.
   virtual bool DoTopControlsShrinkBlinkSize() const;
 
   // The height of the URL-bar top controls.
   virtual float GetTopControlsHeight() const;
 
+  // The height of the bottom bar.
+  virtual float GetBottomControlsHeight() const;
+
   // Called prior to forwarding input event messages to the renderer, giving
   // the view a chance to perform in-process event filtering or processing.
   // Return values of |NOT_CONSUMED| or |UNKNOWN| will result in |input_event|
   // being forwarded.
   virtual InputEventAckState FilterInputEvent(
       const blink::WebInputEvent& input_event);
 
   // Called by the host when it requires an input flush; the flush call should
   // by synchronized with BeginFrame.
   virtual void OnSetNeedsFlushInput();
@@ skipping 305 matching lines @@
   base::ObserverList<RenderWidgetHostViewBaseObserver> observers_;
 
   base::WeakPtrFactory<RenderWidgetHostViewBase> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewBase);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_BASE_H_