Remove unused AudioBuffersState member.

media/audio/audio_buffers_state.cc

-// 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.
-
-#include "media/audio/audio_buffers_state.h"
-
-AudioBuffersState::AudioBuffersState()
-    : pending_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),
-      timestamp(base::Time::Now()) {
-}
-
-int AudioBuffersState::total_bytes() {
-  return pending_bytes + hardware_delay_bytes;
-}