Safe and reliable fix for 2 race conditions.

(We may want to revisit the issue later, implementing more performant one...)

BUG=107933
TEST=Everything should work, and there would be no more crashes in AudioDevice.

Review URL: http://codereview.chromium.org/9112029

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@117464 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 6 insertions, 9 deletions

diff --git a/content/renderer/media/audio_device.cc b/content/renderer/media/audio_device.cc
index 75c2bad..b252d85 100644
--- a/content/renderer/media/audio_device.cc
+++ b/content/renderer/media/audio_device.cc
@@ -106,11 +106,6 @@ void AudioDevice::Start() {
 
 void AudioDevice::Stop() {
   DCHECK(MessageLoop::current() != ChildProcess::current()->io_message_loop());
-  // Max waiting time for Stop() to complete. If this time limit is passed,
-  // we will stop waiting and return false. It ensures that Stop() can't block
-  // the calling thread forever.
-  const base::TimeDelta kMaxTimeOut = base::TimeDelta::FromMilliseconds(1000);
-
   base::WaitableEvent completion(false, false);
 
   ChildProcess::current()->io_message_loop()->PostTask(
@@ -120,9 +115,7 @@ void AudioDevice::Stop() {
   // We wait here for the IO task to be completed to remove race conflicts
   // with OnLowLatencyCreated() and to ensure that Stop() acts as a synchronous
   // function call.
-  if (!completion.TimedWait(kMaxTimeOut)) {
-    LOG(ERROR) << "Failed to shut down audio output on IO thread";
-  }
+  completion.Wait();
   ShutDownAudioThread();
 }
 
diff --git a/content/renderer/media/audio_device.h b/content/renderer/media/audio_device.h
index 559060b..73470b5 100644
--- a/content/renderer/media/audio_device.h
+++ b/content/renderer/media/audio_device.h
@@ -89,7 +89,6 @@ class CONTENT_EXPORT AudioDevice
               int channels,
               double sample_rate,
               RenderCallback* callback);
-  virtual ~AudioDevice();
 
   // AudioRendererSink implementation.
 
@@ -166,6 +165,11 @@ class CONTENT_EXPORT AudioDevice
     base::SyncSocket socket_;
   };
 
+  // Magic required by ref_counted.h to avoid any code deleting the object
+  // accidently while there are references to it.
+  friend class base::RefCountedThreadSafe<AudioDevice>;
+  virtual ~AudioDevice();
+
   // Methods called on IO thread ----------------------------------------------
   // The following methods are tasks posted on the IO thread that needs to
   // be executed on that thread. They interact with AudioMessageFilter and