Deprecate subscriptions to MediaStream ended event

third_party/WebKit/Source/modules/mediastream/MediaStream.cpp

Index: third_party/WebKit/Source/modules/mediastream/MediaStream.cpp
diff --git a/third_party/WebKit/Source/modules/mediastream/MediaStream.cpp b/third_party/WebKit/Source/modules/mediastream/MediaStream.cpp
index 24ef0ac0a7952429e517773fac4dffa481e622e2..a3a84a69708032fc04e97d69d3b2721e9b043ab4 100644
--- a/third_party/WebKit/Source/modules/mediastream/MediaStream.cpp
+++ b/third_party/WebKit/Source/modules/mediastream/MediaStream.cpp
@@ -27,6 +27,7 @@
 
 #include "bindings/core/v8/ExceptionState.h"
 #include "core/dom/ExceptionCode.h"
+#include "core/frame/UseCounter.h"
 #include "modules/mediastream/MediaStreamRegistry.h"
 #include "modules/mediastream/MediaStreamTrackEvent.h"
 #include "platform/mediastream/MediaStreamCenter.h"
@@ -301,6 +302,14 @@ void MediaStream::streamEnded()
     }
 }
 
+bool MediaStream::addEventListenerInternal(const AtomicString& eventType, EventListener* listener, const EventListenerOptions& options)
+{
+    if (eventType == EventTypeNames::ended)
+        UseCounter::count(getExecutionContext(), UseCounter::MediaStreamOnEnded);
+
+    return EventTarget::addEventListenerInternal(eventType, listener, options);

[Rick Byers, 2016/05/05 14:08:57]

nit: This should probably be
"EventTargetWithInlineData::addEventListenerInternal" since this class inherits
from EventTargetWithInlineData (although there's obviously no difference right
now, but just incase we ever overrode addEventListenerInternal in
EventTargetWithInlineData.

+}
+
 void MediaStream::contextDestroyed()
 {
     ContextLifecycleObserver::contextDestroyed();