[Ozone-Dri] Decouple the IO helper thread from DriWrapper

ui/ozone/platform/dri/dri_gpu_platform_support.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 UI_OZONE_PLATFORM_DRI_DRI_GPU_PLATFORM_SUPPORT_H_
 #define UI_OZONE_PLATFORM_DRI_DRI_GPU_PLATFORM_SUPPORT_H_
 
 #include "base/containers/scoped_ptr_hash_map.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
 #include "ipc/message_filter.h"
 #include "ui/gfx/native_widget_types.h"
 #include "ui/ozone/public/gpu_platform_support.h"
 
 class SkBitmap;
 
 namespace base {
 class FilePath;
 }
 
 namespace gfx {
 class Point;
 class Rect;
 }
 
 namespace ui {
 
+class DriHelperThread;
 class DriSurfaceFactory;
 class DriWindowDelegate;
 class DriWindowDelegateManager;
 class DriWrapper;
 class NativeDisplayDelegateDri;
 class ScreenManager;
 
 struct DisplayMode_Params;
 struct DisplaySnapshot_Params;
 
 class DriGpuPlatformSupport : public GpuPlatformSupport {
  public:
   DriGpuPlatformSupport(DriWrapper* drm,
                         DriWindowDelegateManager* window_manager,
                         ScreenManager* screen_manager,
+                        DriHelperThread* helper_thread,
                         scoped_ptr<NativeDisplayDelegateDri> ndd);
   ~DriGpuPlatformSupport() override;
 
   void AddHandler(scoped_ptr<GpuPlatformSupport> handler);
 
   // GpuPlatformSupport:
   void OnChannelEstablished(IPC::Sender* sender) override;
   void RelinquishGpuResources(const base::Closure& callback) override;
   IPC::MessageFilter* GetMessageFilter() override;
 
@@ skipping 29 matching lines @@
   ScreenManager* screen_manager_;             // Not owned.
 
   scoped_ptr<NativeDisplayDelegateDri> ndd_;
   ScopedVector<GpuPlatformSupport> handlers_;
   scoped_refptr<IPC::MessageFilter> filter_;
 };
 
 }  // namespace ui
 
 #endif  // UI_OZONE_PLATFORM_DRI_DRI_GPU_PLATFORM_SUPPORT_H_