conference: stop sink for inputs managed by client

For daemon-managed inputs, the sink stops when the loop
stops. However, for client-managed inputs where the loop
isn't running, cleanup should be invoked upon input
destruction.

Change-Id: Ie4cede2b9e76d6b451139eb897ce94c6da5c2f02

src/media/video/video_input.cpp

@@ -77,6 +77,8 @@ VideoInput::~VideoInput()
 {
     isStopped_ = true;
     if (videoManagedByClient()) {
+        // Stop the video sink for videos that are managed by the client.
+        cleanup();
         emitSignal<libjami::VideoSignal::StopCapture>(decOpts_.input);
         capturing_ = false;
         return;