Adds AudioDevice factory for all audio clients in Chrome

content/renderer/media/audio_message_filter.cc

 // 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.
 
 #include "content/renderer/media/audio_message_filter.h"
 
 #include "base/bind.h"
 #include "base/message_loop.h"
 #include "base/time.h"
 #include "content/common/child_process.h"
 #include "content/common/media/audio_messages.h"
+#include "content/renderer/render_thread_impl.h"
 #include "ipc/ipc_logging.h"
 
+AudioMessageFilter* AudioMessageFilter::filter_ = NULL;
+
+// static
+AudioMessageFilter* AudioMessageFilter::current() {
+  return filter_;
+}
+
 AudioMessageFilter::AudioMessageFilter()
     : channel_(NULL) {
   VLOG(1) << "AudioMessageFilter::AudioMessageFilter()";
+  DCHECK(!filter_);
+  filter_ = this;
 }
 
 int32 AudioMessageFilter::AddDelegate(Delegate* delegate) {
   return delegates_.Add(delegate);
 }
 
 void AudioMessageFilter::RemoveDelegate(int32 id) {
   delegates_.Remove(id);
 }
 
@@ skipping 35 matching lines @@
 void AudioMessageFilter::OnFilterRemoved() {
   channel_ = NULL;
 }
 
 void AudioMessageFilter::OnChannelClosing() {
   channel_ = NULL;
 }
 
 AudioMessageFilter::~AudioMessageFilter() {
   VLOG(1) << "AudioMessageFilter::~AudioMessageFilter()";
+  DCHECK(filter_);
+  filter_ = NULL;
 }
 
 void AudioMessageFilter::OnStreamCreated(
     int stream_id,
     base::SharedMemoryHandle handle,
 #if defined(OS_WIN)
     base::SyncSocket::Handle socket_handle,
 #else
     base::FileDescriptor socket_descriptor,
 #endif
@@ skipping 15 matching lines @@
 void AudioMessageFilter::OnStreamStateChanged(
     int stream_id, AudioStreamState state) {
   Delegate* delegate = delegates_.Lookup(stream_id);
   if (!delegate) {
     DLOG(WARNING) << "Got audio stream event for a non-existent or removed"
         " audio renderer.";
     return;
   }
   delegate->OnStateChanged(state);
 }