Revert of Stall audio thread after device changes to avoid 3rd party deadlock. (patchset #2 id:20001 of https://codereview.chromium.org/1428413003/ )

Reason for revert:
Did not reduce the number of crash reports, so reverting. :(

Original issue's description:
> Stall audio thread after device changes to avoid 3rd party deadlock.
>
> Speculative change to see if stalling callbacks into the Windows
> audio subsystem after a device change is detected will reduce the
> frequency of deadlock in 3rd party WDM drivers.
>
> This change reroutes both input and output device changes through
> the AudioManagerWin, where a simple sleep on the audio thread
> stalls any outstanding activity.
>
> The stall should be fine as the audio thread is used primarily as
> an asychronous control channel. I've chosen a stall over a post
> delayed task to ensure that any outstanding tasks are prevented.
>
> If this CL is successful we can experiment with loosening to a
> PostDelayedTask will still bear fruit.
>
> BUG=422522
> TEST=device change works as normal.
>
> Committed: https://crrev.com/6ffe80ed4dea8b85925ba6dfa2a0cb8f472fb951
> Cr-Commit-Position: refs/heads/master@{#358707}

TBR=watk@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=422522

Review URL: https://codereview.chromium.org/1430423002

Cr-Commit-Position: refs/heads/master@{#358854}

5 files changed, 20 insertions, 52 deletions

diff --git a/media/audio/win/audio_device_listener_win.cc b/media/audio/win/audio_device_listener_win.cc
index 056ab7c..505007b 100644
--- a/media/audio/win/audio_device_listener_win.cc
+++ b/media/audio/win/audio_device_listener_win.cc
@@ -8,6 +8,7 @@
 
 #include "base/logging.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/system_monitor/system_monitor.h"
 #include "base/time/default_tick_clock.h"
 #include "base/win/scoped_co_mem.h"
 #include "base/win/windows_version.h"
@@ -30,7 +31,7 @@ static std::string RoleToString(ERole role) {
   }
 }
 
-AudioDeviceListenerWin::AudioDeviceListenerWin(const ListenerCB& listener_cb)
+AudioDeviceListenerWin::AudioDeviceListenerWin(const base::Closure& listener_cb)
     : listener_cb_(listener_cb), tick_clock_(new base::DefaultTickClock()) {
   CHECK(CoreAudioUtil::IsSupported());
 
@@ -97,7 +98,10 @@ STDMETHODIMP AudioDeviceListenerWin::OnDeviceRemoved(LPCWSTR device_id) {
 
 STDMETHODIMP AudioDeviceListenerWin::OnDeviceStateChanged(LPCWSTR device_id,
                                                           DWORD new_state) {
-  listener_cb_.Run(kInputDeviceChange);
+  base::SystemMonitor* monitor = base::SystemMonitor::Get();
+  if (monitor)
+    monitor->ProcessDevicesChanged(base::SystemMonitor::DEVTYPE_AUDIO_CAPTURE);
+
   return S_OK;
 }
 
@@ -127,7 +131,7 @@ STDMETHODIMP AudioDeviceListenerWin::OnDefaultDeviceChanged(
       now - last_device_change_time_ >
           base::TimeDelta::FromMilliseconds(kDeviceChangeLimitMs)) {
     last_device_change_time_ = now;
-    listener_cb_.Run(kOutputDeviceChange);
+    listener_cb_.Run();
     did_run_listener_cb = true;
   }
 
diff --git a/media/audio/win/audio_device_listener_win.h b/media/audio/win/audio_device_listener_win.h
index 8875269..053afa6 100644
--- a/media/audio/win/audio_device_listener_win.h
+++ b/media/audio/win/audio_device_listener_win.h
@@ -31,14 +31,10 @@ namespace media {
 // TODO(dalecurtis, henrika): Support input device changes.
 class MEDIA_EXPORT AudioDeviceListenerWin : public IMMNotificationClient {
  public:
-  // Callback returns whether input or output devices have changed.
-  enum DeviceNotificationType { kInputDeviceChange, kOutputDeviceChange };
-  using ListenerCB = base::Callback<void(DeviceNotificationType)>;
-
   // The listener callback will be called from a system level multimedia thread,
   // thus the callee must be thread safe.  |listener| is a permanent callback
   // and must outlive AudioDeviceListenerWin.
-  explicit AudioDeviceListenerWin(const ListenerCB& listener_cb);
+  explicit AudioDeviceListenerWin(const base::Closure& listener_cb);
   virtual ~AudioDeviceListenerWin();
 
  private:
@@ -60,7 +56,7 @@ class MEDIA_EXPORT AudioDeviceListenerWin : public IMMNotificationClient {
                                     ERole role,
                                     LPCWSTR new_default_device_id) override;
 
-  ListenerCB listener_cb_;
+  base::Closure listener_cb_;
   ScopedComPtr<IMMDeviceEnumerator> device_enumerator_;
 
   // Used to rate limit device change events.
diff --git a/media/audio/win/audio_device_listener_win_unittest.cc b/media/audio/win/audio_device_listener_win_unittest.cc
index 855c590..4b78d93 100644
--- a/media/audio/win/audio_device_listener_win_unittest.cc
+++ b/media/audio/win/audio_device_listener_win_unittest.cc
@@ -60,8 +60,8 @@ class AudioDeviceListenerWinTest : public testing::Test {
         base::ASCIIToUTF16(new_device_id).c_str()) == S_OK;
   }
 
-  MOCK_METHOD1(OnDeviceChange,
-               void(AudioDeviceListenerWin::DeviceNotificationType));
+
+  MOCK_METHOD0(OnDeviceChange, void());
 
  private:
   ScopedCOMInitializer com_init_;
@@ -75,16 +75,12 @@ class AudioDeviceListenerWinTest : public testing::Test {
 TEST_F(AudioDeviceListenerWinTest, OutputDeviceChange) {
   ABORT_AUDIO_TEST_IF_NOT(CoreAudioUtil::IsSupported());
 
-  EXPECT_CALL(*this,
-              OnDeviceChange(AudioDeviceListenerWin::kOutputDeviceChange))
-      .Times(1);
+  EXPECT_CALL(*this, OnDeviceChange()).Times(1);
   ASSERT_TRUE(SimulateDefaultOutputDeviceChange(kFirstTestDevice));
 
   testing::Mock::VerifyAndClear(this);
   AdvanceLastDeviceChangeTime();
-  EXPECT_CALL(*this,
-              OnDeviceChange(AudioDeviceListenerWin::kOutputDeviceChange))
-      .Times(1);
+  EXPECT_CALL(*this, OnDeviceChange()).Times(1);
   ASSERT_TRUE(SimulateDefaultOutputDeviceChange(kSecondTestDevice));
 
   // The second device event should be ignored since it occurs too soon.
@@ -96,23 +92,17 @@ TEST_F(AudioDeviceListenerWinTest, OutputDeviceChange) {
 TEST_F(AudioDeviceListenerWinTest, NullOutputDeviceChange) {
   ABORT_AUDIO_TEST_IF_NOT(CoreAudioUtil::IsSupported());
 
-  EXPECT_CALL(*this,
-              OnDeviceChange(AudioDeviceListenerWin::kOutputDeviceChange))
-      .Times(1);
+  EXPECT_CALL(*this, OnDeviceChange()).Times(1);
   ASSERT_TRUE(SimulateNullDefaultOutputDeviceChange());
 
   testing::Mock::VerifyAndClear(this);
   AdvanceLastDeviceChangeTime();
-  EXPECT_CALL(*this,
-              OnDeviceChange(AudioDeviceListenerWin::kOutputDeviceChange))
-      .Times(1);
+  EXPECT_CALL(*this, OnDeviceChange()).Times(1);
   ASSERT_TRUE(SimulateDefaultOutputDeviceChange(kFirstTestDevice));
 
   testing::Mock::VerifyAndClear(this);
   AdvanceLastDeviceChangeTime();
-  EXPECT_CALL(*this,
-              OnDeviceChange(AudioDeviceListenerWin::kOutputDeviceChange))
-      .Times(1);
+  EXPECT_CALL(*this, OnDeviceChange()).Times(1);
   ASSERT_TRUE(SimulateNullDefaultOutputDeviceChange());
 }
 
diff --git a/media/audio/win/audio_manager_win.cc b/media/audio/win/audio_manager_win.cc
index 0b97afb..70e6c1b 100644
--- a/media/audio/win/audio_manager_win.cc
+++ b/media/audio/win/audio_manager_win.cc
@@ -21,9 +21,9 @@
 #include "base/process/launch.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
-#include "base/system_monitor/system_monitor.h"
 #include "base/win/windows_version.h"
 #include "media/audio/audio_parameters.h"
+#include "media/audio/win/audio_device_listener_win.h"
 #include "media/audio/win/audio_low_latency_input_win.h"
 #include "media/audio/win/audio_low_latency_output_win.h"
 #include "media/audio/win/audio_manager_win.h"
@@ -171,7 +171,7 @@ void AudioManagerWin::InitializeOnAudioThread() {
     // AudioDeviceListenerWin must be initialized on a COM thread and should
     // only be used if WASAPI / Core Audio is supported.
     output_device_listener_.reset(new AudioDeviceListenerWin(BindToCurrentLoop(
-        base::Bind(&AudioManagerWin::StallAudioThreadAfterDeviceChange,
+        base::Bind(&AudioManagerWin::NotifyAllOutputDeviceChangeListeners,
                    base::Unretained(this)))));
   }
 }
@@ -538,23 +538,6 @@ AudioInputStream* AudioManagerWin::CreatePCMWaveInAudioInputStream(
                                        xp_device_id);
 }
 
-void AudioManagerWin::StallAudioThreadAfterDeviceChange(
-    AudioDeviceListenerWin::DeviceNotificationType notification_type) {
-  base::PlatformThread::Sleep(base::TimeDelta::FromSeconds(1));
-
-  if (notification_type == AudioDeviceListenerWin::kInputDeviceChange) {
-    base::SystemMonitor* monitor = base::SystemMonitor::Get();
-    if (monitor) {
-      monitor->ProcessDevicesChanged(
-          base::SystemMonitor::DEVTYPE_AUDIO_CAPTURE);
-    }
-    return;
-  }
-
-  DCHECK_EQ(notification_type, AudioDeviceListenerWin::kOutputDeviceChange);
-  NotifyAllOutputDeviceChangeListeners();
-}
-
 /// static
 AudioManager* CreateAudioManager(AudioLogFactory* audio_log_factory) {
   return new AudioManagerWin(audio_log_factory);
diff --git a/media/audio/win/audio_manager_win.h b/media/audio/win/audio_manager_win.h
index 3d33b55..9826566 100644
--- a/media/audio/win/audio_manager_win.h
+++ b/media/audio/win/audio_manager_win.h
@@ -8,10 +8,11 @@
 #include <string>
 
 #include "media/audio/audio_manager_base.h"
-#include "media/audio/win/audio_device_listener_win.h"
 
 namespace media {
 
+class AudioDeviceListenerWin;
+
 // Windows implementation of the AudioManager singleton. This class is internal
 // to the audio output and only internal users can call methods not exposed by
 // the AudioManager class.
@@ -87,12 +88,6 @@ class MEDIA_EXPORT AudioManagerWin : public AudioManagerBase {
 
   void GetAudioDeviceNamesImpl(bool input, AudioDeviceNames* device_names);
 
-  // We frequently see deadlock in third party Windows audio drivers, so after
-  // a device change is detected, stall for a second before allowing calls into
-  // the Windows audio subsystem.  See http://crbug.com/422522
-  void StallAudioThreadAfterDeviceChange(
-      AudioDeviceListenerWin::DeviceNotificationType notification_type);
-
   // Listen for output device changes.
   scoped_ptr<AudioDeviceListenerWin> output_device_listener_;