Query the preferred readback config in CopyFromBackingStore

content/browser/frame_host/render_widget_host_view_guest.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 CONTENT_BROWSER_FRAME_HOST_RENDER_WIDGET_HOST_VIEW_GUEST_H_
 #define CONTENT_BROWSER_FRAME_HOST_RENDER_WIDGET_HOST_VIEW_GUEST_H_
 
 #include <vector>
 
 #include "base/memory/scoped_ptr.h"
@@ skipping 144 matching lines @@
   virtual void SetParentNativeViewAccessible(
       gfx::NativeViewAccessible accessible_parent) OVERRIDE;
   virtual gfx::NativeViewId GetParentForWindowlessPlugin() const OVERRIDE;
 #endif
 
   // Overridden from ui::GestureEventHelper.
   virtual bool CanDispatchToConsumer(ui::GestureConsumer* consumer) OVERRIDE;
   virtual void DispatchPostponedGestureEvent(ui::GestureEvent* event) OVERRIDE;
   virtual void DispatchCancelTouchEvent(ui::TouchEvent* event) OVERRIDE;
 
+  virtual SkBitmap::Config PreferredReadbackFormat() OVERRIDE;
+
  protected:
   friend class RenderWidgetHostView;
 
  private:
   // Destroys this view without calling |Destroy| on |platform_view_|.
   void DestroyGuestView();
 
   // Builds and forwards a WebKitGestureEvent to the renderer.
   bool ForwardGestureEventToRenderer(ui::GestureEvent* gesture);
 
@@ skipping 10 matching lines @@
   RenderWidgetHostViewPort* platform_view_;
 #if defined(OS_WIN) || defined(USE_AURA)
   scoped_ptr<ui::GestureRecognizer> gesture_recognizer_;
 #endif  // defined(OS_WIN) || defined(USE_AURA)
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewGuest);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_FRAME_HOST_RENDER_WIDGET_HOST_VIEW_GUEST_H_