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, 3 insertions, 5 deletions

diff --git a/media/audio/audio_input_controller.cc b/media/audio/audio_input_controller.cc
index 27903fa..67623da 100644
--- a/media/audio/audio_input_controller.cc
+++ b/media/audio/audio_input_controller.cc
@@ -103,8 +103,8 @@ void AudioInputController::Record() {
 
 void AudioInputController::Close(const base::Closure& closed_task) {
   DCHECK(!closed_task.is_null());
-  message_loop_->PostTask(FROM_HERE, base::Bind(
-      &AudioInputController::DoClose, this, closed_task));
+  message_loop_->PostTaskAndReply(
+      FROM_HERE, base::Bind(&AudioInputController::DoClose, this), closed_task);
 }
 
 void AudioInputController::DoCreate(AudioManager* audio_manager,
@@ -150,7 +150,7 @@ void AudioInputController::DoRecord() {
   handler_->OnRecording(this);
 }
 
-void AudioInputController::DoClose(const base::Closure& closed_task) {
+void AudioInputController::DoClose() {
   DCHECK(message_loop_->BelongsToCurrentThread());
 
   if (state_ != kClosed) {
@@ -162,8 +162,6 @@ void AudioInputController::DoClose(const base::Closure& closed_task) {
 
     state_ = kClosed;
   }
-
-  closed_task.Run();
 }
 
 void AudioInputController::DoReportError(int code) {