feat(conference): hide user media permission overlay when tracks are created

Don't wait for the connection to be made, since in some cases, when auth is
rquired, for instance, that won't happen until the user inputs their
credentials, but the dialog would be overshadowed by the overlay.

conference.js

@@ -632,11 +632,14 @@ export default {
                 });
         }
 
+        // Hide permissions overlay when tracks are created
+        tryCreateLocalTracks.then(() => {
+            APP.store.dispatch(
+                mediaPermissionPromptVisibilityChanged(false));
+        });
+
         return Promise.all([ tryCreateLocalTracks, connect(roomName) ])
             .then(([ tracks, con ]) => {
-                APP.store.dispatch(
-                    mediaPermissionPromptVisibilityChanged(false));
-
                 // FIXME If there will be microphone error it will cover any
                 // screensharing dialog, but it's still better than in
                 // the reverse order where the screensharing dialog will