Oops, we don't always have a no-show timer.

git-svn-id: svn+ssh://src.earth.threerings.net/vilya/trunk@491 c613c5cb-e716-0410-b11b-feb51c14d237

src/java/com/threerings/parlor/game/server/GameManager.java

@@ -1014,7 +1014,9 @@ public class GameManager extends PlaceManager
     protected void gameDidStart ()
     {
         // clear out our no-show timer if it's still running
-        _noShowInterval.cancel();
+        if (_noShowInterval != null) {
+            _noShowInterval.cancel();
+        }
 
         // let our delegates do their business
         applyToDelegates(new DelegateOp() {