gpu: Add async pixel transfer interface, stub and tests.

gpu/command_buffer/service/gles2_cmd_decoder.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.
 
 // This file contains the GLES2Decoder class.
 
 #ifndef GPU_COMMAND_BUFFER_SERVICE_GLES2_CMD_DECODER_H_
 #define GPU_COMMAND_BUFFER_SERVICE_GLES2_CMD_DECODER_H_
 
 #include <vector>
 
 #include "base/callback.h"
 #include "base/memory/weak_ptr.h"
 #include "base/time.h"
 #include "build/build_config.h"
 #include "gpu/command_buffer/service/common_decoder.h"
 #include "ui/gfx/size.h"
 #include "ui/gl/gl_context.h"
 
 namespace gfx {
 class GLContext;
 class GLSurface;
+class AsyncPixelTransferDelegate;
 }
 
 namespace gpu {
 
 class StreamTextureManager;
 
 namespace gles2 {
 
 class ContextGroup;
 class GLES2Util;
@@ skipping 117 matching lines @@
   // Process any pending queries. Returns false if there are no pending queries.
   virtual bool ProcessPendingQueries() = 0;
 
   // Sets a callback which is called when a glResizeCHROMIUM command
   // is processed.
   virtual void SetResizeCallback(
       const base::Callback<void(gfx::Size)>& callback) = 0;
 
   virtual void SetStreamTextureManager(StreamTextureManager* manager) = 0;
 
+  // Interface to performing async pixel transfers.
+  virtual gfx::AsyncPixelTransferDelegate* GetAsyncPixelTransferDelegate() = 0;
+  virtual void SetAsyncPixelTransferDelegate(
+      gfx::AsyncPixelTransferDelegate* delegate) = 0;
+
   // Get the service texture ID corresponding to a client texture ID.
   // If no such record is found then return false.
   virtual bool GetServiceTextureId(uint32 client_texture_id,
                                    uint32* service_texture_id);
 
   // Provides detail about a lost context if one occurred.
   virtual error::ContextLostReason GetContextLostReason() = 0;
 
   // Clears a level of a texture
   // Returns false if a GL error should be generated.
@@ skipping 35 matching lines @@
   bool log_synthesized_gl_errors_;
   static bool testing_force_is_angle_;
 
   DISALLOW_COPY_AND_ASSIGN(GLES2Decoder);
 };
 
 }  // namespace gles2
 }  // namespace gpu
 
 #endif  // GPU_COMMAND_BUFFER_SERVICE_GLES2_CMD_DECODER_H_