macosx: Use playlist_CurrentInput().

This should fix some race condition of freed input usage.

modules/gui/macosx/intf.m

@@ -1155,7 +1155,7 @@ static VLCMain *_o_sharedMainInstance = nil;
 
         if( p_intf->p_sys->p_input == NULL )
         {
-            p_intf->p_sys->p_input = p_playlist->p_input;
+            p_intf->p_sys->p_input = playlist_CurrentInput( p_playlist );
 
             /* Refresh the interface */
             if( p_intf->p_sys->p_input )
@@ -1170,6 +1170,7 @@ static VLCMain *_o_sharedMainInstance = nil;
             p_intf->p_sys->b_intf_update = true;
             p_intf->p_sys->i_play_status = END_S;
             msg_Dbg( p_intf, "input has stopped, refreshing interface" );
+            vlc_object_release( p_intf->p_sys->p_input );
             p_intf->p_sys->p_input = NULL;
         }