Construct AudioRendererHost in BrowserRendererProcessHost, also construct

ResourceMessageFilter with pointer to it so we can delegate requests to it from IPC later.

Review URL: http://codereview.chromium.org/20131

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@9551 0039d316-1c4b-4281-b951-d872f2087c98

15 files changed, 255 insertions, 18 deletions

diff --git a/chrome/browser/browser.scons b/chrome/browser/browser.scons
index d1dcd6a..de44b18 100644
--- a/chrome/browser/browser.scons
+++ b/chrome/browser/browser.scons
@@ -15,6 +15,7 @@ env.SConscript([
     '$ICU38_DIR/using_icu38.scons',
     '$LIBPNG_DIR/using_libpng.scons',
     '$LIBXML_DIR/using_libxml.scons',
+    '$MEDIA_DIR/using_media.scons',
     '$NPAPI_DIR/using_npapi.scons',
     '$SKIA_DIR/using_skia.scons',
     '$ZLIB_DIR/using_zlib.scons',
@@ -508,6 +509,8 @@ input_files = ChromeFileList([
   MSVSFilter('Renderer Host', [
     'renderer_host/async_resource_handler.cc',
     'renderer_host/async_resource_handler.h',
+    'renderer_host/audio_renderer_host.cc',
+    'renderer_host/audio_renderer_host.h',
     'renderer_host/backing_store.h',
     'renderer_host/backing_store.cc',
     'renderer_host/backing_store_win.cc',
diff --git a/chrome/browser/renderer_host/audio_renderer_host.cc b/chrome/browser/renderer_host/audio_renderer_host.cc
index 66ee9ff..fd798ac 100644
--- a/chrome/browser/renderer_host/audio_renderer_host.cc
+++ b/chrome/browser/renderer_host/audio_renderer_host.cc
@@ -68,18 +68,21 @@ void AudioRendererHost::IPCAudioSource::NotifyPacketReady() {
 
 AudioRendererHost::AudioRendererHost(MessageLoop* message_loop)
     : next_id_(INVALID_ID+1),
-      message_loop_(message_loop) {
+      io_loop_(message_loop) {
+  // Make sure we perform actual initialization operations in the thread where
+  // this object should live.
+  io_loop_->PostTask(FROM_HERE,
+      NewRunnableMethod(this, &AudioRendererHost::OnInitialized));
 }
 
 AudioRendererHost::~AudioRendererHost() {
-  DestroyAllStreams();
 }
 
 int AudioRendererHost::CreateStream(
     IPC::Message::Sender* sender, base::ProcessHandle handle,
     AudioManager::Format format, int channels, int sample_rate,
     int bits_per_sample, size_t packet_size) {
-  DCHECK(MessageLoop::current() == message_loop_);
+  DCHECK(MessageLoop::current() == io_loop_);
 
   // Create the stream in the first place.
   AudioOutputStream* stream = AudioManager::GetAudioManager()->MakeAudioStream(
@@ -100,7 +103,7 @@ int AudioRendererHost::CreateStream(
 }
 
 bool AudioRendererHost::Start(int stream_id) {
-  DCHECK(MessageLoop::current() == message_loop_);
+  DCHECK(MessageLoop::current() == io_loop_);
   IPCAudioSource* source = sources_.Lookup(stream_id);
   if (source) {
     source->stream()->Start(source);
@@ -110,7 +113,7 @@ bool AudioRendererHost::Start(int stream_id) {
 }
 
 bool AudioRendererHost::Stop(int stream_id) {
-  DCHECK(MessageLoop::current() == message_loop_);
+  DCHECK(MessageLoop::current() == io_loop_);
   IPCAudioSource* source = sources_.Lookup(stream_id);
   if (source) {
     source->stream()->Stop();
@@ -120,7 +123,7 @@ bool AudioRendererHost::Stop(int stream_id) {
 }
 
 bool AudioRendererHost::Close(int stream_id) {
-  DCHECK(MessageLoop::current() == message_loop_);
+  DCHECK(MessageLoop::current() == io_loop_);
   IPCAudioSource* source = sources_.Lookup(stream_id);
   if (source) {
     source->stream()->Close();
@@ -131,7 +134,7 @@ bool AudioRendererHost::Close(int stream_id) {
 
 bool AudioRendererHost::SetVolume(
     int stream_id, double left_channel, double right_channel) {
-  DCHECK(MessageLoop::current() == message_loop_);
+  DCHECK(MessageLoop::current() == io_loop_);
   IPCAudioSource* source = sources_.Lookup(stream_id);
   if (source) {
     source->stream()->SetVolume(left_channel, right_channel);
@@ -141,7 +144,7 @@ bool AudioRendererHost::SetVolume(
 
 bool AudioRendererHost::GetVolume(
     int stream_id, double* left_channel, double* right_channel) {
-  DCHECK(MessageLoop::current() == message_loop_);
+  DCHECK(MessageLoop::current() == io_loop_);
   IPCAudioSource* source = sources_.Lookup(stream_id);
   if (source) {
     source->stream()->GetVolume(left_channel, right_channel);
@@ -151,7 +154,7 @@ bool AudioRendererHost::GetVolume(
 }
 
 void AudioRendererHost::NotifyPacketReady(int stream_id) {
-  DCHECK(MessageLoop::current() == message_loop_);
+  DCHECK(MessageLoop::current() == io_loop_);
   IPCAudioSource* source = sources_.Lookup(stream_id);
   if (source) {
     source->NotifyPacketReady();
@@ -159,16 +162,48 @@ void AudioRendererHost::NotifyPacketReady(int stream_id) {
 }
 
 void AudioRendererHost::DestroyAllStreams() {
-  DCHECK(MessageLoop::current() == message_loop_);
+  DCHECK(MessageLoop::current() == io_loop_);
   // TODO(hclam): iterate on the map, close and delete every stream, and clear
   // the map.
 }
 
 void AudioRendererHost::DestroySource(int stream_id) {
-  DCHECK(MessageLoop::current() == message_loop_);
+  DCHECK(MessageLoop::current() == io_loop_);
   IPCAudioSource* source = sources_.Lookup(stream_id);
   if (source) {
     sources_.Remove(stream_id);
     delete source;
   }
 }
+
+void AudioRendererHost::Destroy() {
+  // Post a message to the thread where this object should live and do the
+  // actual operations there.
+  io_loop_->PostTask(
+      FROM_HERE, NewRunnableMethod(this, &AudioRendererHost::OnDestroyed));
+}
+
+void AudioRendererHost::OnInitialized() {
+  DCHECK(MessageLoop::current() == io_loop_);
+
+  // Increase the ref count of this object so it is active until we do
+  // Release().
+  AddRef();
+
+  // Also create the AudioManager singleton in this thread.
+  // TODO(hclam): figure out a better location to initialize the AudioManager
+  // singleton.
+  AudioManager::GetAudioManager();
+}
+
+void AudioRendererHost::OnDestroyed() {
+  DCHECK(MessageLoop::current() == io_loop_);
+
+  // Destroy audio streams only in the thread it should happen.
+  // TODO(hclam): make sure we don't call IPC::Message::Sender inside
+  // IPCAudioSource because it is most likely be destroyed.
+  DestroyAllStreams();
+
+  // Decrease the reference to this object, which may lead to self-destruction.
+  Release();
+}
diff --git a/chrome/browser/renderer_host/audio_renderer_host.h b/chrome/browser/renderer_host/audio_renderer_host.h
index 4df24ba..8128d61 100644
--- a/chrome/browser/renderer_host/audio_renderer_host.h
+++ b/chrome/browser/renderer_host/audio_renderer_host.h
@@ -17,11 +17,31 @@
 // passing a SharedMemoryHandle for filling the buffer.
 // NotifyPacketReady(|stream_id|) would be called when the buffer is filled
 // and ready to be consumed.
+//
+// This class is owned by BrowserRenderProcessHost, and instantiated on UI
+// thread, but all other operations and method calls (except Destroy()) happens
+// in IO thread, so we need to be extra careful about the lifetime of this
+// object. AudioManager is a singleton and created in IO thread, audio output
+// streams are also created in the IO thread, so we need to destroy them also
+// in IO thread. After this class is created, a task of OnInitialized() is
+// posted on IO thread in which singleton of AudioManager is created and
+// AddRef() is called to increase one ref count of this object. Owner of this
+// class should call Destroy() before decrementing the ref count to this object,
+// which essentially post a task of OnDestroyed() on IO thread. Inside
+// OnDestroyed(), audio output streams are destroyed and Release() is called
+// which may result in self-destruction.
+//
+// TODO(hclam): Have these things done before having real implementations:
+//   1. Make sure this class has greater or equal lifetime to
+//      IPC:Message::Sender, essentially ResourceMessageFilter.
+//   2. Listen to destruction event of the browser and do cleanup in case this
+//      class is not destructed nicely during browser close.
 
 #ifndef CHROME_BROWSER_RENDERER_HOST_AUDIO_RENDERER_HOST_H_
 #define CHROME_BROWSER_RENDERER_HOST_AUDIO_RENDERER_HOST_H_
 
 #include "base/id_map.h"
+#include "base/ref_counted.h"
 #include "base/shared_memory.h"
 #include "chrome/common/ipc_message.h"
 #include "media/audio/audio_output.h"
@@ -29,7 +49,7 @@
 class AudioManager;
 class MessageLoop;
 
-class AudioRendererHost {
+class AudioRendererHost : public base::RefCountedThreadSafe<AudioRendererHost> {
  public:
   static const int32 INVALID_ID = 0;
 
@@ -74,14 +94,24 @@ class AudioRendererHost {
   // consumed.
   void NotifyPacketReady(int32 stream_id);
 
-  // Destroy all audio output streams.
-  void DestroyAllStreams();
+  // Called from UI thread from the owner of this object.
+  void Destroy();
 
   // Destroy the stream specified by |stream_id| and remove it from map.
   // *DO NOT* call this method other than from IPCAudioSource.
   void DestroySource(int32 stream_id);
 
  private:
+  // Methods called on IO thread.
+  // Called on IO thread when this object is created and initialized.
+  void OnInitialized();
+  // Called on IO thread when this object needs to be destroyed and after
+  // Destroy() is called from owner of this class in UI thread.
+  void OnDestroyed();
+
+  // Destroy all audio output streams.
+  void DestroyAllStreams();
+
   // The container for AudioOutputStream and serves audio packet for it by IPC.
   class IPCAudioSource : public AudioOutputStream::AudioSourceCallback {
    public:
@@ -124,7 +154,7 @@ class AudioRendererHost {
 
   // Only used for DCHECKs to make sure all methods calls are from the same
   // thread as this object is created.
-  MessageLoop* message_loop_;
+  MessageLoop* io_loop_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioRendererHost);
 };
diff --git a/chrome/browser/renderer_host/audio_renderer_host_unittest.cc b/chrome/browser/renderer_host/audio_renderer_host_unittest.cc
index 443966b..d7ab831 100644
--- a/chrome/browser/renderer_host/audio_renderer_host_unittest.cc
+++ b/chrome/browser/renderer_host/audio_renderer_host_unittest.cc
@@ -11,10 +11,17 @@
 class AudioRendererHostTest : public testing::Test {
  protected:
   virtual void SetUp() {
-    host_.reset(new AudioRendererHost(MessageLoop::current()));
+    // Create a message loop so AudioRendererHost can use it.
+    message_loop_.reset(new MessageLoop(MessageLoop::TYPE_IO));
+    host_ = new AudioRendererHost(MessageLoop::current());
   }
 
-  scoped_ptr<AudioRendererHost> host_;
+  virtual void TearDown() {
+    host_->Destroy();
+  }
+
+  scoped_refptr<AudioRendererHost> host_;
+  scoped_ptr<MessageLoop> message_loop_;
 };
 
 TEST_F(AudioRendererHostTest, NoTest) {
diff --git a/chrome/browser/renderer_host/browser_render_process_host.cc b/chrome/browser/renderer_host/browser_render_process_host.cc
index b020feb..24d5f4d 100644
--- a/chrome/browser/renderer_host/browser_render_process_host.cc
+++ b/chrome/browser/renderer_host/browser_render_process_host.cc
@@ -155,6 +155,10 @@ BrowserRenderProcessHost::~BrowserRenderProcessHost() {
   // We may have some unsent messages at this point, but that's OK.
   channel_.reset();
 
+  // Destroy the AudioRendererHost properly.
+  if (audio_renderer_host_.get())
+    audio_renderer_host_->Destroy();
+
   if (process_.handle() && !run_renderer_in_process()) {
     ProcessWatcher::EnsureProcessTerminated(process_.handle());
   }
@@ -195,8 +199,13 @@ bool BrowserRenderProcessHost::Init() {
   // run the IPC channel on the shared IO thread.
   base::Thread* io_thread = g_browser_process->io_thread();
 
+  // Construct the AudioRendererHost with the IO thread.
+  audio_renderer_host_ =
+      new AudioRendererHost(io_thread->message_loop());
+
   scoped_refptr<ResourceMessageFilter> resource_message_filter =
       new ResourceMessageFilter(g_browser_process->resource_dispatcher_host(),
+                                audio_renderer_host_.get(),
                                 PluginService::GetInstance(),
                                 g_browser_process->print_job_manager(),
                                 host_id(),
diff --git a/chrome/browser/renderer_host/browser_render_process_host.h b/chrome/browser/renderer_host/browser_render_process_host.h
index 3e40d50..d089516 100644
--- a/chrome/browser/renderer_host/browser_render_process_host.h
+++ b/chrome/browser/renderer_host/browser_render_process_host.h
@@ -13,6 +13,7 @@
 #include "base/ref_counted.h"
 #include "base/scoped_ptr.h"
 #include "base/shared_memory.h"
+#include "chrome/browser/renderer_host/audio_renderer_host.h"
 #include "chrome/browser/renderer_host/render_process_host.h"
 #include "chrome/common/notification_observer.h"
 #include "webkit/glue/cache_manager.h"
@@ -136,6 +137,9 @@ class BrowserRenderProcessHost : public RenderProcessHost,
   // IO thread.
   scoped_refptr<RenderWidgetHelper> widget_helper_;
 
+  // The host of audio renderers in the renderer process.
+  scoped_refptr<AudioRendererHost> audio_renderer_host_;
+
   DISALLOW_COPY_AND_ASSIGN(BrowserRenderProcessHost);
 };
 
diff --git a/chrome/browser/renderer_host/resource_message_filter.cc b/chrome/browser/renderer_host/resource_message_filter.cc
index 2db7124..19f0ad9 100644
--- a/chrome/browser/renderer_host/resource_message_filter.cc
+++ b/chrome/browser/renderer_host/resource_message_filter.cc
@@ -13,6 +13,7 @@
 #include "chrome/browser/chrome_thread.h"
 #include "chrome/browser/net/dns_global.h"
 #include "chrome/browser/profile.h"
+#include "chrome/browser/renderer_host/audio_renderer_host.h"
 #include "chrome/browser/renderer_host/browser_render_process_host.h"
 #include "chrome/browser/renderer_host/render_widget_helper.h"
 #include "chrome/common/chrome_plugin_lib.h"
@@ -92,6 +93,7 @@ class WriteClipboardTask : public Task {
 
 ResourceMessageFilter::ResourceMessageFilter(
     ResourceDispatcherHost* resource_dispatcher_host,
+    AudioRendererHost* audio_renderer_host,
     PluginService* plugin_service,
     printing::PrintJobManager* print_job_manager,
     int render_process_host_id,
@@ -108,7 +110,8 @@ ResourceMessageFilter::ResourceMessageFilter(
       render_handle_(NULL),
       request_context_(profile->GetRequestContext()),
       profile_(profile),
-      render_widget_helper_(render_widget_helper) {
+      render_widget_helper_(render_widget_helper),
+      audio_renderer_host_(audio_renderer_host) {
 
   DCHECK(request_context_.get());
   DCHECK(request_context_->cookie_store());
diff --git a/chrome/browser/renderer_host/resource_message_filter.h b/chrome/browser/renderer_host/resource_message_filter.h
index c4d75e3..34d3c3d 100644
--- a/chrome/browser/renderer_host/resource_message_filter.h
+++ b/chrome/browser/renderer_host/resource_message_filter.h
@@ -25,6 +25,7 @@
 #include "chrome/common/temp_scaffolding_stubs.h"
 #endif
 
+class AudioRendererHost;
 class ClipboardService;
 class Profile;
 class RenderWidgetHelper;
@@ -57,6 +58,7 @@ class ResourceMessageFilter : public IPC::ChannelProxy::MessageFilter,
   //        ResourceMessageFilter is 'given' ownership of the spellchecker
   //        object and must clean it up on exit.
   ResourceMessageFilter(ResourceDispatcherHost* resource_dispatcher_host,
+                        AudioRendererHost* audio_renderer_host,
                         PluginService* plugin_service,
                         printing::PrintJobManager* print_job_manager,
                         int render_process_host_id,
@@ -239,6 +241,9 @@ class ResourceMessageFilter : public IPC::ChannelProxy::MessageFilter,
 
   scoped_refptr<RenderWidgetHelper> render_widget_helper_;
 
+  // Object that should take care of audio related resource requests.
+  scoped_refptr<AudioRendererHost> audio_renderer_host_;
+
   DISALLOW_COPY_AND_ASSIGN(ResourceMessageFilter);
 };
 
diff --git a/chrome/chrome.xcodeproj/project.pbxproj b/chrome/chrome.xcodeproj/project.pbxproj
index 7c80e3a..c1d901b 100644
--- a/chrome/chrome.xcodeproj/project.pbxproj
+++ b/chrome/chrome.xcodeproj/project.pbxproj
@@ -286,6 +286,10 @@
 		A7C613C10F30D7E4008CEE5D /* mock_render_process_host.cc in Sources */ = {isa = PBXBuildFile; fileRef = A7C613BF0F30D7E4008CEE5D /* mock_render_process_host.cc */; };
 		A7C6146F0F30DA1D008CEE5D /* ipc_test_sink.cc in Sources */ = {isa = PBXBuildFile; fileRef = A7C6146D0F30DA1D008CEE5D /* ipc_test_sink.cc */; };
 		A7CBAD390F322A7E00360BF5 /* shell_dialogs_mac.mm in Sources */ = {isa = PBXBuildFile; fileRef = A7CBAD370F322A7E00360BF5 /* shell_dialogs_mac.mm */; };
+		ABFA33770F424E47008FCF5D /* audio_renderer_host.cc in Sources */ = {isa = PBXBuildFile; fileRef = ABFA33740F424E06008FCF5D /* audio_renderer_host.cc */; };
+		ABFA34C50F4255CC008FCF5D /* libmedia.a in Frameworks */ = {isa = PBXBuildFile; fileRef = ABFA33880F424EC5008FCF5D /* libmedia.a */; };
+		ABFA34C70F425637008FCF5D /* libmedia.a in Frameworks */ = {isa = PBXBuildFile; fileRef = ABFA33880F424EC5008FCF5D /* libmedia.a */; };
+		ABFA34C80F425677008FCF5D /* libmedia.a in Frameworks */ = {isa = PBXBuildFile; fileRef = ABFA33880F424EC5008FCF5D /* libmedia.a */; };
 		B0AC9501DED2809AC208AEEA /* resolve_proxy_msg_helper.cc in Sources */ = {isa = PBXBuildFile; fileRef = 4F9429998AC2703984BAB828 /* resolve_proxy_msg_helper.cc */; };
 		B502DA280F098056005BE90C /* visit_database_unittest.cc in Sources */ = {isa = PBXBuildFile; fileRef = 4D7BFA180E9D48F7009A6919 /* visit_database_unittest.cc */; };
 		B502DA520F098888005BE90C /* l10n_util.cc in Sources */ = {isa = PBXBuildFile; fileRef = 4D7BFBC90E9D4C9F009A6919 /* l10n_util.cc */; };
@@ -1536,6 +1540,41 @@
 			remoteGlobalIDString = 7BA361A60E8C36E50023C8B9;
 			remoteInfo = sdch;
 		};
+		ABFA33870F424EC5008FCF5D /* PBXContainerItemProxy */ = {
+			isa = PBXContainerItemProxy;
+			containerPortal = ABFA33790F424EC5008FCF5D /* media.xcodeproj */;
+			proxyType = 2;
+			remoteGlobalIDString = E4BA04540E25613300BE02C6 /* libmedia.a */;
+			remoteInfo = media;
+		};
+		ABFA33890F424EC5008FCF5D /* PBXContainerItemProxy */ = {
+			isa = PBXContainerItemProxy;
+			containerPortal = ABFA33790F424EC5008FCF5D /* media.xcodeproj */;
+			proxyType = 2;
+			remoteGlobalIDString = E4AFA6230E523E2900201347 /* media_unittests */;
+			remoteInfo = media_unittests;
+		};
+		ABFA338D0F424F39008FCF5D /* PBXContainerItemProxy */ = {
+			isa = PBXContainerItemProxy;
+			containerPortal = ABFA33790F424EC5008FCF5D /* media.xcodeproj */;
+			proxyType = 1;
+			remoteGlobalIDString = D2AAC045055464E500DB518D /* media */;
+			remoteInfo = media;
+		};
+		ABFA33DA0F4252CD008FCF5D /* PBXContainerItemProxy */ = {
+			isa = PBXContainerItemProxy;
+			containerPortal = ABFA33790F424EC5008FCF5D /* media.xcodeproj */;
+			proxyType = 1;
+			remoteGlobalIDString = D2AAC045055464E500DB518D /* media */;
+			remoteInfo = media;
+		};
+		ABFA34C90F425694008FCF5D /* PBXContainerItemProxy */ = {
+			isa = PBXContainerItemProxy;
+			containerPortal = ABFA33790F424EC5008FCF5D /* media.xcodeproj */;
+			proxyType = 1;
+			remoteGlobalIDString = D2AAC045055464E500DB518D /* media */;
+			remoteInfo = media;
+		};
 		B503E1010F017BE300547DC6 /* PBXContainerItemProxy */ = {
 			isa = PBXContainerItemProxy;
 			containerPortal = 4D7BF2E90E9D46A4009A6919 /* Project object */;
@@ -2366,6 +2405,10 @@
 		A7C6146E0F30DA1D008CEE5D /* ipc_test_sink.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = ipc_test_sink.h; sourceTree = "<group>"; };
 		A7CBAD370F322A7E00360BF5 /* shell_dialogs_mac.mm */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.objcpp; name = shell_dialogs_mac.mm; path = cocoa/shell_dialogs_mac.mm; sourceTree = "<group>"; };
 		A9C335E39D39A7DE087850FC /* url_pattern_unittest.cc */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = url_pattern_unittest.cc; path = common/extensions/url_pattern_unittest.cc; sourceTree = SOURCE_ROOT; };
+		ABFA33740F424E06008FCF5D /* audio_renderer_host.cc */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = audio_renderer_host.cc; path = renderer_host/audio_renderer_host.cc; sourceTree = "<group>"; };
+		ABFA33750F424E06008FCF5D /* audio_renderer_host.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = audio_renderer_host.h; path = renderer_host/audio_renderer_host.h; sourceTree = "<group>"; };
+		ABFA33760F424E06008FCF5D /* audio_renderer_host_unittest.cc */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = audio_renderer_host_unittest.cc; path = renderer_host/audio_renderer_host_unittest.cc; sourceTree = "<group>"; };
+		ABFA33790F424EC5008FCF5D /* media.xcodeproj */ = {isa = PBXFileReference; lastKnownFileType = "wrapper.pb-project"; name = media.xcodeproj; path = media/media.xcodeproj; sourceTree = "<group>"; };
 		B51F6D110F37C4DC00152D66 /* renderer_main_platform_delegate.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = renderer_main_platform_delegate.h; sourceTree = "<group>"; };
 		B51F6D120F37C4DC00152D66 /* renderer_main_platform_delegate_win.cc */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = renderer_main_platform_delegate_win.cc; sourceTree = "<group>"; };
 		B51F6D130F37C4DC00152D66 /* renderer_main_platform_delegate_mac.cc */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = renderer_main_platform_delegate_mac.cc; sourceTree = "<group>"; };
@@ -2693,6 +2736,7 @@
 				4D7BFF3A0E9D5378009A6919 /* libjpeg.a in Frameworks */,
 				E477F6B70F4095660044ABEB /* libjsbindings.a in Frameworks */,
 				E477F6B80F4095660044ABEB /* libjscre.a in Frameworks */,
+				ABFA34C80F425677008FCF5D /* libmedia.a in Frameworks */,
 				4D7B005E0E9D54BB009A6919 /* libmodp_b64.a in Frameworks */,
 				4D7B00510E9D5473009A6919 /* libnet.a in Frameworks */,
 				E477F6B90F4095660044ABEB /* libpcre.a in Frameworks */,
@@ -2746,6 +2790,7 @@
 				331218460F3C024A006CB2B0 /* libjpeg.a in Frameworks */,
 				E4DCDC9F0F40938D0084059A /* libjsbindings.a in Frameworks */,
 				E4DCDCA00F40938D0084059A /* libjscre.a in Frameworks */,
+				ABFA34C70F425637008FCF5D /* libmedia.a in Frameworks */,
 				33121A470F3C037E006CB2B0 /* libmodp_b64.a in Frameworks */,
 				331218410F3C0208006CB2B0 /* libnet.a in Frameworks */,
 				E4DCDCA10F40938D0084059A /* libpcre.a in Frameworks */,
@@ -2809,6 +2854,7 @@
 				E45062AC0EE89154003BE099 /* libicuuc.a in Frameworks */,
 				E4DCDC910F40929C0084059A /* libjsbindings.a in Frameworks */,
 				E4DCDC970F4092C10084059A /* libjscre.a in Frameworks */,
+				ABFA34C50F4255CC008FCF5D /* libmedia.a in Frameworks */,
 				E48B67CB0F262607002E47EC /* libmodp_b64.a in Frameworks */,
 				E48B66A80F26257E002E47EC /* libnet.a in Frameworks */,
 				E4DCDC920F40929C0084059A /* libpcre.a in Frameworks */,
@@ -3451,6 +3497,7 @@
 				4D1F5AB10F2A6EE90040C1E3 /* libpng.xcodeproj */,
 				4D7BFB0B0E9D4BBF009A6919 /* libxml.xcodeproj */,
 				826850600F2FCC27009F6555 /* libxslt.xcodeproj */,
+				ABFA33790F424EC5008FCF5D /* media.xcodeproj */,
 				4D7B00580E9D54AA009A6919 /* modp_b64.xcodeproj */,
 				4D7B00340E9D5464009A6919 /* net.xcodeproj */,
 				82684D050F2FB101009F6555 /* sdch.xcodeproj */,
@@ -3856,6 +3903,15 @@
 			name = debugger;
 			sourceTree = "<group>";
 		};
+		ABFA337A0F424EC5008FCF5D /* Products */ = {
+			isa = PBXGroup;
+			children = (
+				ABFA33880F424EC5008FCF5D /* libmedia.a */,
+				ABFA338A0F424EC5008FCF5D /* media_unittests */,
+			);
+			name = Products;
+			sourceTree = "<group>";
+		};
 		B555B20F0F21503700F751B9 /* metrics */ = {
 			isa = PBXGroup;
 			children = (
@@ -4109,6 +4165,9 @@
 		E45075D80F150A3B003BE099 /* renderer_host */ = {
 			isa = PBXGroup;
 			children = (
+				ABFA33740F424E06008FCF5D /* audio_renderer_host.cc */,
+				ABFA33750F424E06008FCF5D /* audio_renderer_host.h */,
+				ABFA33760F424E06008FCF5D /* audio_renderer_host_unittest.cc */,
 				E45075DA0F150A53003BE099 /* async_resource_handler.cc */,
 				E45075DB0F150A53003BE099 /* async_resource_handler.h */,
 				A7C613C40F30D82C008CEE5D /* backing_store.cc */,
@@ -4363,6 +4422,7 @@
 				4D7BFE780E9D52EB009A6919 /* PBXTargetDependency */,
 				4D7BFF580E9D53D2009A6919 /* PBXTargetDependency */,
 				4D7BFF390E9D536D009A6919 /* PBXTargetDependency */,
+				ABFA34CA0F425694008FCF5D /* PBXTargetDependency */,
 				4D7B00600E9D54BF009A6919 /* PBXTargetDependency */,
 				4D7B00560E9D5487009A6919 /* PBXTargetDependency */,
 				B503E1020F017BE300547DC6 /* PBXTargetDependency */,
@@ -4436,6 +4496,7 @@
 				33121F090F3CF47F006CB2B0 /* PBXTargetDependency */,
 				33121F0B0F3CF47F006CB2B0 /* PBXTargetDependency */,
 				33121F0D0F3CF47F006CB2B0 /* PBXTargetDependency */,
+				ABFA338E0F424F39008FCF5D /* PBXTargetDependency */,
 				33121F0F0F3CF47F006CB2B0 /* PBXTargetDependency */,
 				33121F110F3CF47F006CB2B0 /* PBXTargetDependency */,
 				33121F130F3CF47F006CB2B0 /* PBXTargetDependency */,
@@ -4502,6 +4563,7 @@
 				E45062A00EE8912D003BE099 /* PBXTargetDependency */,
 				E45062A40EE8912D003BE099 /* PBXTargetDependency */,
 				E46C4EB10F278A3000B393B8 /* PBXTargetDependency */,
+				ABFA33DB0F4252CD008FCF5D /* PBXTargetDependency */,
 				E46C4EB50F278A4800B393B8 /* PBXTargetDependency */,
 				E46C4EB90F278A7100B393B8 /* PBXTargetDependency */,
 				E450631A0EE990C4003BE099 /* PBXTargetDependency */,
@@ -4584,6 +4646,10 @@
 					ProjectRef = 826850600F2FCC27009F6555 /* libxslt.xcodeproj */;
 				},
 				{
+					ProductGroup = ABFA337A0F424EC5008FCF5D /* Products */;
+					ProjectRef = ABFA33790F424EC5008FCF5D /* media.xcodeproj */;
+				},
+				{
 					ProductGroup = 4D7B00590E9D54AA009A6919 /* Products */;
 					ProjectRef = 4D7B00580E9D54AA009A6919 /* modp_b64.xcodeproj */;
 				},
@@ -4916,6 +4982,20 @@
 			remoteRef = 826850690F2FCC27009F6555 /* PBXContainerItemProxy */;
 			sourceTree = BUILT_PRODUCTS_DIR;
 		};
+		ABFA33880F424EC5008FCF5D /* libmedia.a */ = {
+			isa = PBXReferenceProxy;
+			fileType = archive.ar;
+			path = libmedia.a;
+			remoteRef = ABFA33870F424EC5008FCF5D /* PBXContainerItemProxy */;
+			sourceTree = BUILT_PRODUCTS_DIR;
+		};
+		ABFA338A0F424EC5008FCF5D /* media_unittests */ = {
+			isa = PBXReferenceProxy;
+			fileType = "compiled.mach-o.executable";
+			path = media_unittests;
+			remoteRef = ABFA33890F424EC5008FCF5D /* PBXContainerItemProxy */;
+			sourceTree = BUILT_PRODUCTS_DIR;
+		};
 /* End PBXReferenceProxy section */
 
 /* Begin PBXResourcesBuildPhase section */
@@ -5128,6 +5208,7 @@
 			files = (
 				4D7BFA1E0E9D48FD009A6919 /* archived_database.cc in Sources */,
 				E45075DC0F150A53003BE099 /* async_resource_handler.cc in Sources */,
+				ABFA33770F424E47008FCF5D /* audio_renderer_host.cc in Sources */,
 				6D62D71064BA3204EF0A964A /* autofill_manager.cc in Sources */,
 				E43A770B0F1660EA00ABD5D1 /* automation_resource_tracker.cc in Sources */,
 				E434BFD90F3A074300B665C7 /* backing_store.cc in Sources */,
@@ -5946,6 +6027,21 @@
 			name = sdch;
 			targetProxy = 8268521A0F2FD197009F6555 /* PBXContainerItemProxy */;
 		};
+		ABFA338E0F424F39008FCF5D /* PBXTargetDependency */ = {
+			isa = PBXTargetDependency;
+			name = media;
+			targetProxy = ABFA338D0F424F39008FCF5D /* PBXContainerItemProxy */;
+		};
+		ABFA33DB0F4252CD008FCF5D /* PBXTargetDependency */ = {
+			isa = PBXTargetDependency;
+			name = media;
+			targetProxy = ABFA33DA0F4252CD008FCF5D /* PBXContainerItemProxy */;
+		};
+		ABFA34CA0F425694008FCF5D /* PBXTargetDependency */ = {
+			isa = PBXTargetDependency;
+			name = media;
+			targetProxy = ABFA34C90F425694008FCF5D /* PBXContainerItemProxy */;
+		};
 		B503E1020F017BE300547DC6 /* PBXTargetDependency */ = {
 			isa = PBXTargetDependency;
 			target = 4D640CEA0EAE86BD00EBCFC0 /* renderer */;
diff --git a/chrome/test/unit/unit_tests.scons b/chrome/test/unit/unit_tests.scons
index 814cea8..2f19de8 100644
--- a/chrome/test/unit/unit_tests.scons
+++ b/chrome/test/unit/unit_tests.scons
@@ -22,6 +22,7 @@ env.SConscript([
     '$LIBXML_DIR/using_libxml.scons',
     '$LIBXSLT_DIR/using_libxslt.scons',
     '$MODP_B64_DIR/using_modp_b64.scons',
+    '$MEDIA_DIR/using_media.scons',
     '$NET_DIR/using_net.scons',
     '$NPAPI_DIR/using_npapi.scons',
     '$SDCH_DIR/using_sdch.scons',
diff --git a/media/audio/audio_output.h b/media/audio/audio_output.h
index b21d653..7d82500 100644
--- a/media/audio/audio_output.h
+++ b/media/audio/audio_output.h
@@ -5,6 +5,8 @@
 #ifndef MEDIA_AUDIO_AUDIO_OUTPUT_H_
 #define MEDIA_AUDIO_AUDIO_OUTPUT_H_
 
+#include "base/basictypes.h"
+
 // Low-level audio output support. To make sound there are 3 objects involved:
 // - AudioSource : produces audio samples on a pull model. Implements
 //   the AudioSourceCallback interface.
diff --git a/media/audio/linux/audio_manager_linux.cc b/media/audio/linux/audio_manager_linux.cc
new file mode 100644
index 0000000..15a13b2
--- /dev/null
+++ b/media/audio/linux/audio_manager_linux.cc
@@ -0,0 +1,10 @@
+// Copyright (c) 2006-2009 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_output.h"
+
+// TODO(hclam): Do something more useful than returning NULL.
+AudioManager* AudioManager::GetAudioManager() {
+  return NULL;
+}
diff --git a/media/audio/mac/audio_manager_mac.cc b/media/audio/mac/audio_manager_mac.cc
new file mode 100644
index 0000000..15a13b2
--- /dev/null
+++ b/media/audio/mac/audio_manager_mac.cc
@@ -0,0 +1,10 @@
+// Copyright (c) 2006-2009 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_output.h"
+
+// TODO(hclam): Do something more useful than returning NULL.
+AudioManager* AudioManager::GetAudioManager() {
+  return NULL;
+}
diff --git a/media/media.xcodeproj/project.pbxproj b/media/media.xcodeproj/project.pbxproj
index 488391e..91e425c 100644
--- a/media/media.xcodeproj/project.pbxproj
+++ b/media/media.xcodeproj/project.pbxproj
@@ -46,6 +46,7 @@
 		8200F2030E5F741E005A3C44 /* CoreServices.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 8200F2020E5F741E005A3C44 /* CoreServices.framework */; };
 		820706940EB8D9D4005CD9E7 /* SystemConfiguration.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 820706930EB8D9D4005CD9E7 /* SystemConfiguration.framework */; };
 		82113A280E84360200E3848F /* Security.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 82113A270E84360200E3848F /* Security.framework */; };
+		ABFA33A30F424FBD008FCF5D /* audio_manager_mac.cc in Sources */ = {isa = PBXBuildFile; fileRef = ABFA33A20F424FBD008FCF5D /* audio_manager_mac.cc */; };
 		DC5E24F40EFC4CE5006AD1A7 /* data_buffer.cc in Sources */ = {isa = PBXBuildFile; fileRef = DC5E24E10EFC4CC8006AD1A7 /* data_buffer.cc */; };
 		DC5E24F50EFC4CE5006AD1A7 /* media_format.cc in Sources */ = {isa = PBXBuildFile; fileRef = DC5E24E60EFC4CC8006AD1A7 /* media_format.cc */; };
 		DC5E24F60EFC4CF7006AD1A7 /* data_buffer_unittest.cc in Sources */ = {isa = PBXBuildFile; fileRef = DC5E24E30EFC4CC8006AD1A7 /* data_buffer_unittest.cc */; };
@@ -225,6 +226,7 @@
 		8200F2020E5F741E005A3C44 /* CoreServices.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = CoreServices.framework; path = System/Library/Frameworks/CoreServices.framework; sourceTree = "<group>"; };
 		820706930EB8D9D4005CD9E7 /* SystemConfiguration.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = SystemConfiguration.framework; path = /System/Library/Frameworks/SystemConfiguration.framework; sourceTree = "<absolute>"; };
 		82113A270E84360200E3848F /* Security.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = Security.framework; path = System/Library/Frameworks/Security.framework; sourceTree = "<group>"; };
+		ABFA33A20F424FBD008FCF5D /* audio_manager_mac.cc */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = audio_manager_mac.cc; path = mac/audio_manager_mac.cc; sourceTree = "<group>"; };
 		DC5E24DE0EFC4CC8006AD1A7 /* audio_output.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = audio_output.h; sourceTree = "<group>"; };
 		DC5E24E00EFC4CC8006AD1A7 /* buffers.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = buffers.h; sourceTree = "<group>"; };
 		DC5E24E10EFC4CC8006AD1A7 /* data_buffer.cc */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = data_buffer.cc; sourceTree = "<group>"; };
@@ -373,9 +375,18 @@
 			name = Products;
 			sourceTree = "<group>";
 		};
+		ABFA33980F424FAF008FCF5D /* mac */ = {
+			isa = PBXGroup;
+			children = (
+				ABFA33A20F424FBD008FCF5D /* audio_manager_mac.cc */,
+			);
+			name = mac;
+			sourceTree = "<group>";
+		};
 		DC5E24DD0EFC4CC8006AD1A7 /* audio */ = {
 			isa = PBXGroup;
 			children = (
+				ABFA33980F424FAF008FCF5D /* mac */,
 				DC5E24DE0EFC4CC8006AD1A7 /* audio_output.h */,
 			);
 			path = audio;
@@ -620,6 +631,7 @@
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				ABFA33A30F424FBD008FCF5D /* audio_manager_mac.cc in Sources */,
 				DC5E24F40EFC4CE5006AD1A7 /* data_buffer.cc in Sources */,
 				DC66E6E30F13FE6A00E13554 /* filter_host_impl.cc in Sources */,
 				DC5E24F50EFC4CE5006AD1A7 /* media_format.cc in Sources */,
diff --git a/media/media_lib.scons b/media/media_lib.scons
index 0e017b1..51676b1 100644
--- a/media/media_lib.scons
+++ b/media/media_lib.scons
@@ -56,6 +56,16 @@ input_files = ChromeFileList([
   ]),
 ])
 
+if env.Bit('linux'):
+  input_files.Extend([
+      'audio/linux/audio_manager_linux.cc',
+  ])
+
+if env.Bit('mac'):
+  input_files.Extend([
+      'audio/mac/audio_manager_mac.cc',
+  ])
+
 if not env.Bit('windows'):
   # Windows-specific files.
   input_files.Remove(