Revert of MediaCaptureFromElement: add support for audio captureStream().

media/blink/webaudiosourceprovider_impl.cc

Index: media/blink/webaudiosourceprovider_impl.cc
diff --git a/media/blink/webaudiosourceprovider_impl.cc b/media/blink/webaudiosourceprovider_impl.cc
index 31bb5aa11b69a46ee5fe1507fd9290907117c65b..3f052dbeb6f5a8f9759964cb534635f5e19ebd79 100644
--- a/media/blink/webaudiosourceprovider_impl.cc
+++ b/media/blink/webaudiosourceprovider_impl.cc
@@ -233,10 +233,6 @@
 void WebAudioSourceProviderImpl::SetCopyAudioCallback(
     const CopyAudioCB& callback) {
   DCHECK(!callback.is_null());
-
-  // Use |sink_lock_| to protect |tee_filter_| too since they go in lockstep.
-  base::AutoLock auto_lock(sink_lock_);
-
   DCHECK(tee_filter_);
   tee_filter_->set_copy_audio_bus_callback(callback);
 }
@@ -244,19 +240,19 @@
 void WebAudioSourceProviderImpl::ClearCopyAudioCallback() {
   DCHECK(tee_filter_);
   tee_filter_->set_copy_audio_bus_callback(CopyAudioCB());
+}
+
+void WebAudioSourceProviderImpl::OnSetFormat() {
+  base::AutoLock auto_lock(sink_lock_);
+  if (!client_)
+    return;
+
+  // Inform Blink about the audio stream format.
+  client_->setFormat(tee_filter_->channels(), tee_filter_->sample_rate());
 }
 
 int WebAudioSourceProviderImpl::RenderForTesting(AudioBus* audio_bus) {
   return tee_filter_->Render(audio_bus, 0, 0);
-}
-
-void WebAudioSourceProviderImpl::OnSetFormat() {
-  base::AutoLock auto_lock(sink_lock_);
-  if (!client_)
-    return;
-
-  // Inform Blink about the audio stream format.
-  client_->setFormat(tee_filter_->channels(), tee_filter_->sample_rate());
 }
 
 int WebAudioSourceProviderImpl::TeeFilter::Render(AudioBus* audio_bus,