update the talking status of the video window when the user leaves the audio

bigbluebutton-client/src/org/bigbluebutton/modules/videoconf/views/UserGraphicHolder.mxml

@@ -242,6 +242,7 @@ with BigBlueButton; if not, see <http://www.gnu.org/licenses/>.
             private function handleUserVoiceChangedEvent(event:BBBEvent):void {
                 if (user && event.payload.userID == user.userID) {
                     updateButtons();
+                    updateTalkingStatus();
                 }
             }