Notify GUI of x-run counter resets

libs/ardour/ardour/session.h

@@ -825,7 +825,7 @@ public:
 	void maybe_update_tempo_from_midiclock_tempo (float bpm);
 
 	unsigned int    get_xrun_count () const {return _xrun_count; }
-	void            reset_xrun_count () {_xrun_count = 0; }
+	void            reset_xrun_count ();
 
 	/* region info  */
 

libs/ardour/session_transport.cc

@@ -1811,6 +1811,13 @@ Session::xrun_recovery ()
 	}
 }
 
+void
+Session::reset_xrun_count ()
+{
+	_xrun_count = 0;
+	Xrun (-1); /* EMIT SIGNAL */
+}
+
 void
 Session::route_processors_changed (RouteProcessorChange c)
 {