Revert 126474 - Remove unused AudioBuffersState member.

Review URL: http://codereview.chromium.org/9689015

TBR=enal@chromium.org
Review URL: https://chromiumcodereview.appspot.com/9692067

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@126478 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 21 insertions, 9 deletions

diff --git a/media/audio/audio_buffers_state.cc b/media/audio/audio_buffers_state.cc
index 7e829fe..f31cf1d 100644
--- a/media/audio/audio_buffers_state.cc
+++ b/media/audio/audio_buffers_state.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright (c) 2010 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.
 
@@ -6,11 +6,17 @@
 
 AudioBuffersState::AudioBuffersState()
     : pending_bytes(0),
-      hardware_delay_bytes(0) {
+      hardware_delay_bytes(0),
+      timestamp(base::Time::Now()) {
 }
 
 AudioBuffersState::AudioBuffersState(int pending_bytes,
                                      int hardware_delay_bytes)
     : pending_bytes(pending_bytes),
-      hardware_delay_bytes(hardware_delay_bytes) {
+      hardware_delay_bytes(hardware_delay_bytes),
+      timestamp(base::Time::Now()) {
+}
+
+int AudioBuffersState::total_bytes() {
+  return pending_bytes + hardware_delay_bytes;
 }
diff --git a/media/audio/audio_buffers_state.h b/media/audio/audio_buffers_state.h
index a7299e1..796c081 100644
--- a/media/audio/audio_buffers_state.h
+++ b/media/audio/audio_buffers_state.h
@@ -1,21 +1,21 @@
-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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_AUDIO_AUDIO_BUFFERS_STATE_H_
 #define MEDIA_AUDIO_AUDIO_BUFFERS_STATE_H_
 
+#include "base/time.h"
 #include "media/base/media_export.h"
 
-// AudioBuffersState struct stores current state of audio buffers.
-// It is used for audio synchronization.
+// AudioBuffersState struct stores current state of audio buffers along with
+// the timestamp of the moment this state corresponds to. It is used for audio
+// synchronization.
 struct MEDIA_EXPORT AudioBuffersState {
   AudioBuffersState();
   AudioBuffersState(int pending_bytes, int hardware_delay_bytes);
 
-  int total_bytes() {
-    return pending_bytes + hardware_delay_bytes;
-  }
+  int total_bytes();
 
   // Number of bytes we currently have in our software buffer.
   int pending_bytes;
@@ -23,6 +23,12 @@ struct MEDIA_EXPORT AudioBuffersState {
   // Number of bytes that have been written to the device, but haven't
   // been played yet.
   int hardware_delay_bytes;
+
+  // Timestamp of the moment when the buffers state was captured. It is used
+  // to account for the time it takes to deliver AudioBuffersState from
+  // the browser process to the renderer.
+  base::Time timestamp;
 };
 
+
 #endif  // MEDIA_AUDIO_AUDIO_BUFFERS_STATE_H_