Update talk to 61538839.

TBR=mallinath

Review URL: https://webrtc-codereview.appspot.com/8669005

git-svn-id: http://webrtc.googlecode.com/svn/trunk@5548 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/talk/app/webrtc/remoteaudiosource.h b/talk/app/webrtc/remoteaudiosource.h
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+++ b/talk/app/webrtc/remoteaudiosource.h
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+/*
+ * libjingle
+ * Copyright 2014, Google Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *  1. Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *  2. Redistributions in binary form must reproduce the above copyright notice,
+ *     this list of conditions and the following disclaimer in the documentation
+ *     and/or other materials provided with the distribution.
+ *  3. The name of the author may not be used to endorse or promote products
+ *     derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef TALK_APP_WEBRTC_REMOTEAUDIOSOURCE_H_
+#define TALK_APP_WEBRTC_REMOTEAUDIOSOURCE_H_
+
+#include <list>
+
+#include "talk/app/webrtc/mediastreaminterface.h"
+#include "talk/app/webrtc/notifier.h"
+
+namespace webrtc {
+
+using webrtc::AudioSourceInterface;
+
+// This class implements the audio source used by the remote audio track.
+class RemoteAudioSource : public Notifier<AudioSourceInterface> {
+ public:
+  // Creates an instance of RemoteAudioSource.
+  static talk_base::scoped_refptr<RemoteAudioSource> Create();
+
+ protected:
+  RemoteAudioSource();
+  virtual ~RemoteAudioSource();
+
+ private:
+  typedef std::list<AudioObserver*> AudioObserverList;
+
+  // MediaSourceInterface implementation.
+  virtual MediaSourceInterface::SourceState state() const OVERRIDE;
+
+  // AudioSourceInterface implementation.
+  virtual void SetVolume(double volume) OVERRIDE;
+  virtual void RegisterAudioObserver(AudioObserver* observer) OVERRIDE;
+  virtual void UnregisterAudioObserver(AudioObserver* observer) OVERRIDE;
+
+  AudioObserverList audio_observers_;
+};
+
+}  // namespace webrtc
+
+#endif  // TALK_APP_WEBRTC_REMOTEAUDIOSOURCE_H_