Fix AEC3 override to set once only when creating MediaStreamAudioProcessor.

* Add AecDumpMessageFilter::GetOverrideAec3().
* Don't set aec3 in AecDumpMessageFilter::AddDelegate().
* Instead, get the override value before init in MSAP.
* In init, the override value is already honored, although that was always not set before this fix.

Bug: 791016
Change-Id: I0d58ab3dac13321b4a686b6f726c449930b185d5
Reviewed-on: https://chromium-review.googlesource.com/803486Reviewed-by: Max Morin <maxmorin@chromium.org>
Commit-Queue: Henrik Grunell <grunell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#520958}

content/renderer/media/aec_dump_message_filter.cc

@@ -48,10 +48,6 @@ void AecDumpMessageFilter::AddDelegate(
   int id = delegate_id_counter_++;
   delegates_[id] = delegate;
 
-  if (override_aec3_) {
-    delegate->OnAec3Enable(*override_aec3_);
-  }
-
   io_task_runner_->PostTask(
       FROM_HERE,
       base::BindOnce(&AecDumpMessageFilter::RegisterAecDumpConsumer, this, id));
@@ -72,6 +68,11 @@ void AecDumpMessageFilter::RemoveDelegate(
                      id));
 }
 
+base::Optional<bool> AecDumpMessageFilter::GetOverrideAec3() const {
+  DCHECK(main_task_runner_->BelongsToCurrentThread());
+  return override_aec3_;
+}
+
 void AecDumpMessageFilter::Send(IPC::Message* message) {
   DCHECK(io_task_runner_->BelongsToCurrentThread());
   if (sender_)

content/renderer/media/aec_dump_message_filter.h

@@ -8,6 +8,7 @@
 #include <memory>
 
 #include "base/macros.h"
+#include "base/optional.h"
 #include "content/common/content_export.h"
 #include "content/renderer/render_thread_impl.h"
 #include "ipc/ipc_platform_file.h"
@@ -40,10 +41,13 @@ class CONTENT_EXPORT AecDumpMessageFilter : public IPC::MessageFilter {
   // Getter for the one AecDumpMessageFilter object.
   static scoped_refptr<AecDumpMessageFilter> Get();
 
-  // Adds a delegate that receives the enable and disable notifications.
+  // Adds a delegate that receives the enable and disable notifications. Must be
+  // called on the main task runner (|main_task_runner| in constructor). All
+  // calls on |delegate| are done on the main task runner.
   void AddDelegate(AecDumpMessageFilter::AecDumpDelegate* delegate);
 
-  // Removes a delegate.
+  // Removes a delegate. Must be called on the main task runner
+  // (|main_task_runner| in constructor).
   void RemoveDelegate(AecDumpMessageFilter::AecDumpDelegate* delegate);
 
   // IO task runner associated with this message filter.
@@ -51,6 +55,10 @@ class CONTENT_EXPORT AecDumpMessageFilter : public IPC::MessageFilter {
     return io_task_runner_;
   }
 
+  // Returns the AEC3 setting. Must be called on the main task runner
+  // (|main_task_runner| in constructor).
+  base::Optional<bool> GetOverrideAec3() const;
+
  protected:
   ~AecDumpMessageFilter() override;
 

content/renderer/media/media_stream_audio_processor.cc

@@ -320,12 +320,17 @@ MediaStreamAudioProcessor::MediaStreamAudioProcessor(
   DCHECK(main_thread_runner_);
   capture_thread_checker_.DetachFromThread();
   render_thread_checker_.DetachFromThread();
-  InitializeAudioProcessingModule(properties);
 
-  aec_dump_message_filter_ = AecDumpMessageFilter::Get();
   // In unit tests not creating a message filter, |aec_dump_message_filter_|
-  // will be NULL. We can just ignore that. Other unit tests and browser tests
-  // ensure that we do get the filter when we should.
+  // will be null. We can just ignore that below. Other unit tests and browser
+  // tests ensure that we do get the filter when we should.
+  aec_dump_message_filter_ = AecDumpMessageFilter::Get();
+
+  if (aec_dump_message_filter_)
+    override_aec3_ = aec_dump_message_filter_->GetOverrideAec3();
+
+  InitializeAudioProcessingModule(properties);
+
   if (aec_dump_message_filter_.get())
     aec_dump_message_filter_->AddDelegate(this);