media::WebAudioSourceProviderImpl, add support for getting a copy of passing AudioBuses

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 5b70a3091ba7760878c7f5d9f80147af4a1292c6..142b450fe5d25eacb0e160992876664424d9800a 100644
--- a/media/blink/webaudiosourceprovider_impl.cc
+++ b/media/blink/webaudiosourceprovider_impl.cc
@@ -53,8 +53,8 @@ WebAudioSourceProviderImpl::WebAudioSourceProviderImpl(
       sample_rate_(0),
       volume_(1.0),
       state_(kStopped),
-      renderer_(NULL),
-      client_(NULL),
+      renderer_(nullptr),
+      client_(nullptr),
       sink_(sink),
       weak_factory_(this) {}
 
@@ -172,12 +172,13 @@ OutputDevice* WebAudioSourceProviderImpl::GetOutputDevice() {
 
 void WebAudioSourceProviderImpl::Initialize(
     const AudioParameters& params,
-    RenderCallback* renderer) {
+    AudioRendererSink::RenderCallback* renderer) {
   base::AutoLock auto_lock(sink_lock_);
+
   renderer_ = renderer;
 
   DCHECK_EQ(state_, kStopped);
-  sink_->Initialize(params, renderer);
+  sink_->Initialize(params, this);  // We act as forwarder to |renderer_|.
 
   // Keep track of the format in case the client hasn't yet been set.
   channels_ = params.channels();
@@ -187,6 +188,42 @@ void WebAudioSourceProviderImpl::Initialize(
     base::ResetAndReturn(&set_format_cb_).Run();
 }
 
+int WebAudioSourceProviderImpl::Render(AudioBus* audio_bus,
+                                       uint32_t delay_milliseconds,
+                                       uint32_t frames_skipped) {
+  DCHECK(renderer_);
+  DCHECK(!frames_skipped);

[DaleCurtis, 2016/03/11 01:41:42]

Is this reasonable?

[mcasas, 2016/03/11 04:06:23]

Prob remainder of some test. Removed.

+
+  const int num_rendered_frames =
+      renderer_->Render(audio_bus, delay_milliseconds, frames_skipped);
+
+  if (!onaudiobus_callback_.is_null()) {
+    scoped_ptr<AudioBus> bus_copy =
+        AudioBus::Create(audio_bus->channels(), audio_bus->frames());
+    audio_bus->CopyTo(bus_copy.get());
+    onaudiobus_callback_.Run(std::move(bus_copy), delay_milliseconds);
+  }
+
+  return num_rendered_frames;
+}
+
+void WebAudioSourceProviderImpl::OnRenderError() {
+  DCHECK(renderer_);
+  renderer_->OnRenderError();
+}
+
+void WebAudioSourceProviderImpl::RegisterOnAudioBusCallback(
+    const OnAudioBusCB& callback) {
+  DCHECK(!callback.is_null());
+  DCHECK(onaudiobus_callback_.is_null());
+  onaudiobus_callback_ = callback;
+}
+
+void WebAudioSourceProviderImpl::ResetOnAudioBusCallback() {
+  DCHECK(!onaudiobus_callback_.is_null());
+  onaudiobus_callback_.Reset();
+}
+
 void WebAudioSourceProviderImpl::OnSetFormat() {
   base::AutoLock auto_lock(sink_lock_);
   if (!client_)