Ensure the wedge timer isn't started until after StartStream().

media/audio/audio_output_controller.cc

Index: media/audio/audio_output_controller.cc
diff --git a/media/audio/audio_output_controller.cc b/media/audio/audio_output_controller.cc
index 74853e09492418e8a233e3dd99b051fd3d4609d5..1e7892660b775125686e5f7843407a057f7f0095 100644
--- a/media/audio/audio_output_controller.cc
+++ b/media/audio/audio_output_controller.cc
@@ -198,6 +198,9 @@ void AudioOutputController::DoPlay() {
   power_poll_callback_.callback().Run();
 #endif
 
+  AllowEntryToOnMoreIOData();
+  stream_->Start(this);
+
   // For UMA tracking purposes, start the wedge detection timer.  This allows us
   // to record statistics about the number of wedged playbacks in the field.
   //
@@ -215,9 +218,6 @@ void AudioOutputController::DoPlay() {
       &AudioOutputController::WedgeCheck);
   on_more_io_data_called_ = 0;

[miu, 2013/11/07 23:18:41]

Should this statement (setting on_more_io_data_called_ to 0) occur before
AllowEntryToOnMoreIOData() above?  It's possible, in a race condition, for
on_more_io_data_called_ to be incremented on the audio device thread, and then
set back to zero on this thread, right?

[DaleCurtis, 2013/11/07 23:22:54]

Good catch!

 
-  AllowEntryToOnMoreIOData();
-  stream_->Start(this);
-
   handler_->OnPlaying();
 }