mozilla: fix compilation after [1979486d]

projects/mozilla/control/npolibvlc.cpp

@@ -218,8 +218,7 @@ LibvlcAudioNPObject::getProperty(int index, NPVariant &result)
         {
             case ID_audio_mute:
             {
-                bool muted = libvlc_audio_get_mute(p_plugin->getVLC(), &ex);
-                RETURN_ON_EXCEPTION(this,ex);
+                bool muted = libvlc_audio_get_mute(p_plugin->getVLC());
                 BOOLEAN_TO_NPVARIANT(muted, result);
                 return INVOKERESULT_NO_ERROR;
             }

projects/mozilla/vlcshell.cpp

@@ -855,8 +855,7 @@ static void ControlHandler( Widget w, XtPointer closure, XEvent *event )
             case clicked_Mute:
             case clicked_Unmute:
             {
-                libvlc_audio_toggle_mute( p_plugin->getVLC(), &ex );
-                libvlc_exception_clear( &ex );
+                libvlc_audio_toggle_mute( p_plugin->getVLC() );
             }
             break;