[mutter] stack-tracker: Fix the case where the serial is too old

[Jasper St. Pierre <jstpierre src gnome org>]

commit d1a588a94fba75c21a6b26b30a73c2087ad0c4e5
Author: Jasper St. Pierre <jstpierre mecheye net>
Date:   Thu Jul 10 15:58:46 2014 -0400

    stack-tracker: Fix the case where the serial is too old
    
    The code here before was just flat out wrong, and made us consistently
    requery the server at startup.

 src/core/stack-tracker.c |   13 +++++--------
 1 files changed, 5 insertions(+), 8 deletions(-)
---
diff --git a/src/core/stack-tracker.c b/src/core/stack-tracker.c
index a10506b..9e99241 100644
--- a/src/core/stack-tracker.c
+++ b/src/core/stack-tracker.c
@@ -1037,15 +1037,12 @@ stack_tracker_event_received (MetaStackTracker *tracker,
   gboolean need_sync = FALSE;
   gboolean verified;
 
-  meta_stack_op_dump (op, "Stack op event received: ", "\n");
-
+  /* If the event is older than our latest requery, then it's
+   * already included in our tree. Just ignore it. */
   if (op->any.serial < tracker->xserver_serial)
-    {
-      /* g_warning ("Spurious X event received affecting stack; doing full re-query"); */
-      resync_verified_stack_with_xserver_stack (tracker);
-      meta_stack_tracker_dump (tracker);
-      return;
-    }
+    return;
+
+  meta_stack_op_dump (op, "Stack op event received: ", "\n");
 
   tracker->xserver_serial = op->any.serial;