Tracks all open input streams in AudioManagerBase.

media/audio/audio_manager_base.cc

Index: media/audio/audio_manager_base.cc
diff --git a/media/audio/audio_manager_base.cc b/media/audio/audio_manager_base.cc
index 944156c66c6f8e9eb1e561ea1896b01a9c05a083..f182a9d08bebb5e5c1e6b778cbd927fe1bbea3b1 100644
--- a/media/audio/audio_manager_base.cc
+++ b/media/audio/audio_manager_base.cc
@@ -82,7 +82,6 @@ AudioManagerBase::AudioManagerBase(
       max_num_output_streams_(kDefaultMaxOutputStreams),
       max_num_input_streams_(kDefaultMaxInputStreams),
       num_output_streams_(0),
-      num_input_streams_(0),
       // TODO(dalecurtis): Switch this to an base::ObserverListThreadSafe, so we
       // don't
       // block the UI thread when swapping devices.
@@ -96,7 +95,7 @@ AudioManagerBase::~AudioManagerBase() {
   // All the output streams should have been deleted.
   CHECK_EQ(0, num_output_streams_);
   // All the input streams should have been deleted.
-  CHECK_EQ(0, num_input_streams_);
+  CHECK(input_streams_.empty());
 }
 
 base::string16 AudioManagerBase::GetAudioInputDeviceModel() {
@@ -163,10 +162,10 @@ AudioInputStream* AudioManagerBase::MakeAudioInputStream(
     return NULL;
   }
 
-  if (num_input_streams_ >= max_num_input_streams_) {
+  if (input_stream_count() >= max_num_input_streams_) {
     DLOG(ERROR) << "Number of opened input audio streams "
-                << num_input_streams_
-                << " exceed the max allowed number " << max_num_input_streams_;
+                << input_stream_count() << " exceed the max allowed number "
+                << max_num_input_streams_;
     return NULL;
   }
 
@@ -190,7 +189,7 @@ AudioInputStream* AudioManagerBase::MakeAudioInputStream(
   }
 
   if (stream) {
-    ++num_input_streams_;
+    input_streams_.insert(stream);
   }
 
   return stream;
@@ -282,6 +281,7 @@ void AudioManagerBase::GetAudioOutputDeviceNames(
 
 void AudioManagerBase::ReleaseOutputStream(AudioOutputStream* stream) {
   DCHECK(stream);
+  CHECK_GT(num_output_streams_, 0);
   // TODO(xians) : Have a clearer destruction path for the AudioOutputStream.
   // For example, pass the ownership to AudioManager so it can delete the
   // streams.
@@ -292,7 +292,7 @@ void AudioManagerBase::ReleaseOutputStream(AudioOutputStream* stream) {
 void AudioManagerBase::ReleaseInputStream(AudioInputStream* stream) {
   DCHECK(stream);
   // TODO(xians) : Have a clearer destruction path for the AudioInputStream.
-  --num_input_streams_;
+  CHECK_EQ(1u, input_streams_.erase(stream));
   delete stream;
 }
 
@@ -303,6 +303,20 @@ void AudioManagerBase::Shutdown() {
     output_dispatchers_.back()->dispatcher->Shutdown();
     output_dispatchers_.pop_back();
   }
+
+#if defined(OS_MACOSX)
+  // On mac, AudioManager runs on the main thread, loop for which stops
+  // processing task queue at this point. So even if tasks to close the
+  // streams are enqueued, they would not run leading to CHECKs getting hit
+  // in the destructor about open streams. Close them explicitly here.
+  // crbug.com/608049.
+  for (auto iter = input_streams_.begin(); iter != input_streams_.end();) {
+    // Note: Closing the stream will invalidate the iterator.
+    // Increment the iterator before closing the stream.
+    AudioInputStream* stream = *iter++;
+    stream->Close();
+  }
+#endif  // OS_MACOSX
 }
 
 void AudioManagerBase::AddOutputDeviceChangeListener(