Fix race in AudioInputController::Close().

Before this change, a reference to AudioInputController was bound into the
Callback invoking DoClose(), which executes on the audio thread.  If the
audio thread is slow to delete that callback (after dispatching |closed_task|)
then the main thread's reference to the AudioInputController might be released
first, leading to AudioInputController being destructed on the audio thread,
triggering a DCHECK in Timer::~Timer() (owned by the AudioInputController via
DelayTimer).

This race was exposed while working on http://codereview.chromium.org/9717021/
but isn't so much related to the content of that CL as to the fact that that CL
twiddles callback lifetime/timing a bit.


Review URL: http://codereview.chromium.org/9839051

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@128495 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 6 insertions, 13 deletions

diff --git a/media/audio/audio_input_controller_unittest.cc b/media/audio/audio_input_controller_unittest.cc
index 250f7c8..869610e 100644
--- a/media/audio/audio_input_controller_unittest.cc
+++ b/media/audio/audio_input_controller_unittest.cc
@@ -37,10 +37,8 @@ ACTION_P3(CheckCountAndPostQuitTask, count, limit, loop_or_proxy) {
 
 // Closes AudioOutputController synchronously.
 static void CloseAudioController(AudioInputController* controller) {
-  base::WaitableEvent closed_event(true, false);
-  controller->Close(base::Bind(&base::WaitableEvent::Signal,
-                               base::Unretained(&closed_event)));
-  closed_event.Wait();
+  controller->Close(MessageLoop::QuitClosure());
+  MessageLoop::current()->Run();
 }
 
 class MockAudioInputControllerEventHandler
@@ -216,16 +214,11 @@ TEST_F(AudioInputControllerTest, CloseTwice) {
 
   controller->Record();
 
-  base::WaitableEvent closed_event_1(true, false);
-  controller->Close(base::Bind(&base::WaitableEvent::Signal,
-                               base::Unretained(&closed_event_1)));
+  controller->Close(MessageLoop::QuitClosure());
+  MessageLoop::current()->Run();
 
-  base::WaitableEvent closed_event_2(true, false);
-  controller->Close(base::Bind(&base::WaitableEvent::Signal,
-                               base::Unretained(&closed_event_2)));
-
-  closed_event_1.Wait();
-  closed_event_2.Wait();
+  controller->Close(MessageLoop::QuitClosure());
+  MessageLoop::current()->Run();
 }
 
 }  // namespace media