Query the preferred readback config in CopyFromBackingStore

content/browser/renderer_host/render_widget_host_view_aura.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_AURA_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_AURA_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 366 matching lines @@
                                     base::TimeTicks start_time) OVERRIDE;
   virtual void OnCompositingEnded(ui::Compositor* compositor) OVERRIDE;
   virtual void OnCompositingAborted(ui::Compositor* compositor) OVERRIDE;
   virtual void OnCompositingLockStateChanged(
       ui::Compositor* compositor) OVERRIDE;
 
   // Overridden from ui::CompositorVSyncManager::Observer
   virtual void OnUpdateVSyncParameters(base::TimeTicks timebase,
                                        base::TimeDelta interval) OVERRIDE;
 
+  virtual SkBitmap::Config PreferredReadbackFormat() OVERRIDE;
+
  private:
   FRIEND_TEST_ALL_PREFIXES(RenderWidgetHostViewAuraTest, SetCompositionText);
   FRIEND_TEST_ALL_PREFIXES(RenderWidgetHostViewAuraTest, TouchEventState);
   FRIEND_TEST_ALL_PREFIXES(RenderWidgetHostViewAuraTest, TouchEventSyncAsync);
   FRIEND_TEST_ALL_PREFIXES(RenderWidgetHostViewAuraTest, SwapNotifiesWindow);
   FRIEND_TEST_ALL_PREFIXES(RenderWidgetHostViewAuraTest,
                            SkippedDelegatedFrames);
   FRIEND_TEST_ALL_PREFIXES(RenderWidgetHostViewAuraTest, OutputSurfaceIdChange);
   FRIEND_TEST_ALL_PREFIXES(RenderWidgetHostViewAuraTest,
                            DiscardDelegatedFrames);
@@ skipping 393 matching lines @@
   // etc.
   scoped_ptr<content::LegacyRenderWidgetHostHWND>
       legacy_render_widget_host_HWND_;
 #endif
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostViewAura);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_VIEW_AURA_H_