Move audio decoding to protocol layer

remoting/protocol/connection_to_host.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 REMOTING_PROTOCOL_CONNECTION_TO_HOST_H_
 #define REMOTING_PROTOCOL_CONNECTION_TO_HOST_H_
 
 #include <memory>
 #include <string>
 
 #include "base/memory/ref_counted.h"
+#include "base/memory/weak_ptr.h"
 #include "remoting/protocol/errors.h"
 
+namespace base {
+class SingleThreadTaskRunner;
+}  // namespace base
+
 namespace remoting {
 namespace protocol {
 
 class AudioStub;
 class Authenticator;
 class ClientStub;
 class ClipboardStub;
 class HostStub;
 class InputStub;
 class Session;
@@ skipping 40 matching lines @@
 
   virtual ~ConnectionToHost() {}
 
   // Set the stubs which will handle messages from the host.
   // The caller must ensure that stubs out-live the connection.
   // Unless otherwise specified, all stubs must be set before Connect()
   // is called.
   virtual void set_client_stub(ClientStub* client_stub) = 0;
   virtual void set_clipboard_stub(ClipboardStub* clipboard_stub) = 0;
   virtual void set_video_renderer(VideoRenderer* video_renderer) = 0;
-  // If no audio stub is specified then audio will not be requested.
-  virtual void set_audio_stub(AudioStub* audio_stub) = 0;
+
+  // Initializes audio stream. Must be called before Connect().
+  // |audio_decode_task_runner| will be used for audio decoding. |audio_stub|
+  // will be called on the main thread.
+  virtual void InitializeAudio(
+      scoped_refptr<base::SingleThreadTaskRunner> audio_decode_task_runner,
+      base::WeakPtr<AudioStub> audio_stub) = 0;
 
   // Initiates a connection using |session|. |event_callback| will be notified
   // of changes in the state of the connection and must outlive the
   // ConnectionToHost. Caller must set stubs (see below) before calling Connect.
   virtual void Connect(std::unique_ptr<Session> session,
                        scoped_refptr<TransportContext> transport_context,
                        HostEventCallback* event_callback) = 0;
 
   // Returns the session configuration that was negotiated with the host.
   virtual const SessionConfig& config() = 0;
 
   // Stubs for sending data to the host.
   virtual ClipboardStub* clipboard_forwarder() = 0;
   virtual HostStub* host_stub() = 0;
   virtual InputStub* input_stub() = 0;
 
   // Return the current state of ConnectionToHost.
   virtual State state() const = 0;
 };
 
 }  // namespace protocol
 }  // namespace remoting
 
 #endif  // REMOTING_PROTOCOL_CONNECTION_TO_HOST_H_