cc: Add CopyAsBitmapRequest class to hold the readback callback.

cc/output/direct_renderer.h

 // Copyright 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 CC_OUTPUT_DIRECT_RENDERER_H_
 #define CC_OUTPUT_DIRECT_RENDERER_H_
 
 #include "base/basictypes.h"
 #include "base/callback.h"
 #include "cc/base/cc_export.h"
@@ skipping 94 matching lines @@
   virtual void SetScissorTestRect(gfx::Rect scissor_rect) = 0;
   virtual void ClearFramebuffer(DrawingFrame* frame) = 0;
   virtual void DoDrawQuad(DrawingFrame* frame, const DrawQuad* quad) = 0;
   virtual void BeginDrawingFrame(DrawingFrame* frame) = 0;
   virtual void FinishDrawingFrame(DrawingFrame* frame) = 0;
   virtual void FinishDrawingQuadList();
   virtual bool FlippedFramebuffer() const = 0;
   virtual void EnsureScissorTestEnabled() = 0;
   virtual void EnsureScissorTestDisabled() = 0;
 
-  typedef base::Callback<void(scoped_ptr<SkBitmap>)>
-      CopyRenderPassCallback;
   virtual void CopyCurrentRenderPassToBitmap(
       DrawingFrame* frame,
-      const CopyRenderPassCallback& callback) = 0;
+      scoped_ptr<CopyOutputRequest> request) = 0;
 
   ScopedPtrHashMap<RenderPass::Id, CachedResource> render_pass_textures_;
   ResourceProvider* resource_provider_;
 
  private:
   gfx::Vector2d enlarge_pass_texture_amount_;
 
   DISALLOW_COPY_AND_ASSIGN(DirectRenderer);
 };
 
 }  // namespace cc
 
 #endif  // CC_OUTPUT_DIRECT_RENDERER_H_