Do DXVA pre-sandbox initialization off the main thread.

content/common/gpu/media/dxva_video_decode_accelerator.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_COMMON_GPU_MEDIA_DXVA_VIDEO_DECODE_ACCELERATOR_H_
 #define CONTENT_COMMON_GPU_MEDIA_DXVA_VIDEO_DECODE_ACCELERATOR_H_
 
 #include <d3d9.h>
 #include <dxva2api.h>
 #include <list>
@@ skipping 43 matching lines @@
   virtual void ReusePictureBuffer(int32 picture_buffer_id) OVERRIDE;
   virtual void Flush() OVERRIDE;
   virtual void Reset() OVERRIDE;
   virtual void Destroy() OVERRIDE;
 
   // Initialization work needed before the process is sandboxed.
   // This includes:-
   // 1. Loads the dlls like mf/mfplat/d3d9, etc required for decoding.
   // 2. Setting up the device manager instance which is shared between all
   //    decoder instances.
-  static void PreSandboxInitialization();
+  // Invokes the completion task, potentially on another thread, when complete.
+  static void PreSandboxInitialization(
+      const base::Closure& completion_task);
 
  private:
   typedef void* EGLConfig;
   typedef void* EGLSurface;
   // Creates and initializes an instance of the D3D device and the
   // corresponding device manager. The device manager instance is eventually
   // passed to the IMFTransform interface implemented by the h.264 decoder.
-  static bool CreateD3DDevManager();
+  // Invokes the completion task, potentially on another thread, when complete.
+  static void CreateD3DDevManager(
+      const base::Closure& completion_task);
 
   // Creates, initializes and sets the media types for the h.264 decoder.
   bool InitDecoder();
 
   // Validates whether the h.264 decoder supports hardware video acceleration.
   bool CheckDecoderDxvaSupport();
 
   // Returns information about the input and output streams. This includes
   // alignment information, decoder support flags, minimum sample size, etc.
   bool GetStreamsInfoAndBufferReqs();
@@ skipping 132 matching lines @@
   typedef std::list<media::BitstreamBuffer> PendingInputs;
   PendingInputs pending_input_buffers_;
 
   // Callback to set the correct gl context.
   base::Callback<bool(void)> make_context_current_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_GPU_MEDIA_DXVA_VIDEO_DECODE_ACCELERATOR_H_