media: Use PassInterface() in mojo media classes

media/mojo/services/mojo_audio_decoder.h

 // Copyright 2016 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 MEDIA_MOJO_SERVICES_MOJO_AUDIO_DECODER_H_
 #define MEDIA_MOJO_SERVICES_MOJO_AUDIO_DECODER_H_
 
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "media/base/audio_decoder.h"
 #include "media/mojo/interfaces/audio_decoder.mojom.h"
 #include "mojo/public/cpp/bindings/binding.h"
+#include "mojo/public/cpp/bindings/interface_ptr_info.h"
 #include "mojo/public/cpp/system/data_pipe.h"
 
 namespace base {
 class SingleThreadTaskRunner;
 }
 
 namespace media {
 
 // An AudioDecoder that proxies to an interfaces::AudioDecoder.
 class MojoAudioDecoder : public AudioDecoder,
@@ skipping 33 matching lines @@
   // A helper method that creates data pipe and sets the data connection to
   // the service.
   void CreateDataPipe();
 
   // A helper method to serialize the data section of DecoderBuffer into pipe.
   interfaces::DecoderBufferPtr TransferDecoderBuffer(
       const scoped_refptr<DecoderBuffer>& media_buffer);
 
   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;
 
+  // This class is constructed on one thread and used exclusively on another
+  // thread. This member is used to safely pass the AudioDecoderPtr from one
+  // thread to another. It is set in the constructor and is consumed in
+  // Initialize().
+  mojo::InterfacePtrInfo<interfaces::AudioDecoder> remote_decoder_info_;

[yzshen1, 2016/03/22 19:15:04]

optional: you could use interfaces::AudioDecoderPtrInfo as the type name, too.

[xhwang, 2016/03/22 19:45:26]

Done.

+
   interfaces::AudioDecoderPtr remote_decoder_;
 
   // DataPipe for serializing the data section of DecoderBuffer.
   mojo::ScopedDataPipeProducerHandle producer_handle_;
 
   // Binding for AudioDecoderClient, bound to the |task_runner_|.
   mojo::Binding<AudioDecoderClient> binding_;
 
   // We call the following callbacks to pass the information to the pipeline.
   // |output_cb_| is permanent while other three are called only once,
   // |decode_cb_| and |reset_cb_| are replaced by every by Decode() and Reset().
   InitCB init_cb_;
   OutputCB output_cb_;
   DecodeCB decode_cb_;
   base::Closure reset_cb_;
 
   // Flag that is set if we got connection error. Never cleared.
   bool has_connection_error_;
 
   // Flag telling whether this decoder requires bitstream conversion.
   // Passed from |remote_decoder_| as a result of its initialization.
   bool needs_bitstream_conversion_;
 
   DISALLOW_COPY_AND_ASSIGN(MojoAudioDecoder);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_MOJO_SERVICES_MOJO_AUDIO_DECODER_H_