MediaStream audio: Refactor 3 separate "glue" implementations into one.

content/renderer/media/media_stream_source.cc

Index: content/renderer/media/media_stream_source.cc
diff --git a/content/renderer/media/media_stream_source.cc b/content/renderer/media/media_stream_source.cc
index 8db26024403334efc43050ce36a75bc06301362b..d2b4cbf7f9bac1af284e581a6887e78578ff08ec 100644
--- a/content/renderer/media/media_stream_source.cc
+++ b/content/renderer/media/media_stream_source.cc
@@ -13,14 +13,41 @@ const char MediaStreamSource::kSourceId[] = "sourceId";
 MediaStreamSource::MediaStreamSource() {
 }
 
-MediaStreamSource::~MediaStreamSource() {}
+MediaStreamSource::~MediaStreamSource() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  RunStopCallbackAndEndStream();
+}
 
 void MediaStreamSource::StopSource() {
+  DCHECK(thread_checker_.CalledOnValidThread());
   DoStopSource();
+  RunStopCallbackAndEndStream();
+}
+
+void MediaStreamSource::SetDeviceInfo(const StreamDeviceInfo& device_info) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  device_info_ = device_info;
+}
+
+void MediaStreamSource::SetStopCallback(
+    const SourceStoppedCallback& stop_callback) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(stop_callback_.is_null());
+  stop_callback_ = stop_callback;
+}
+
+void MediaStreamSource::ResetSourceStoppedCallback() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(!stop_callback_.is_null());
+  stop_callback_.Reset();
+}
+
+void MediaStreamSource::RunStopCallbackAndEndStream() {
+  DCHECK(thread_checker_.CalledOnValidThread());
   if (!stop_callback_.is_null())
     base::ResetAndReturn(&stop_callback_).Run(owner());
-
-  owner().setReadyState(blink::WebMediaStreamSource::ReadyStateEnded);
+  if (!owner().isNull())
+    owner().setReadyState(blink::WebMediaStreamSource::ReadyStateEnded);
 }
 
 }  // namespace content