Bug 1172394 - Forward direct listeners to all inputs over a ForwardedInputTrack's lifetime. r=padenot

This was not needed when inputs to a ForwardedInputTrack could not come and go,
but they can now. This keeps direct listeners for a ForwardedInputTrack around
until it ends, as that's the terminal state where we know we can no longer
process another input.

Depends on D52049

Differential Revision: https://phabricator.services.mozilla.com/D53015

--HG--
extra : moz-landing-system : lando

dom/media/ForwardedInputTrack.cpp

@@ -60,11 +60,6 @@ void ForwardedInputTrack::RemoveInput(MediaInputPort* aPort) {
   TRACK_LOG(LogLevel::Debug,
             ("ForwardedInputTrack %p removing input %p", this, aPort));
   MOZ_ASSERT(aPort == mInputPort);
-  nsTArray<RefPtr<DirectMediaTrackListener>> listeners(mOwnedDirectListeners);
-  for (const auto& listener : listeners) {
-    // Remove listeners while the entry still exists.
-    RemoveDirectListenerImpl(listener);
-  }
   mInputPort = nullptr;
   ProcessedMediaTrack::RemoveInput(aPort);
 }
@@ -163,6 +158,10 @@ void ForwardedInputTrack::ProcessInput(GraphTime aFrom, GraphTime aTo,
   } else {
     MOZ_CRASH("Unknown segment type");
   }
+
+  if (mEnded) {
+    RemoveAllDirectListenersImpl();
+  }
 }
 
 void ForwardedInputTrack::SetEnabledImpl(DisabledTrackMode aMode) {