1 files changed, 5 insertions, 2 deletions
diff --git a/services/sync/tps/extensions/mozmill/resource/modules/assertions.js b/services/sync/tps/extensions/mozmill/resource/modules/assertions.js
index b49502057..c76f95747 100644
--- a/services/sync/tps/extensions/mozmill/resource/modules/assertions.js
+++ b/services/sync/tps/extensions/mozmill/resource/modules/assertions.js
@@ -4,7 +4,7 @@
 
 var EXPORTED_SYMBOLS = ['Assert', 'Expect'];
 
-const Cu = Components.utils;
+var Cu = Components.utils;
 
 Cu.import("resource://gre/modules/Services.jsm");
 
@@ -658,7 +658,10 @@ Expect.prototype.waitFor = function Expect_waitFor(aCallback, aMessage, aTimeout
   try {
     Assert.prototype.waitFor.apply(this, arguments);
   }
-  catch (ex if ex instanceof errors.AssertionError) {
+  catch (ex) {
+    if (!(ex instanceof errors.AssertionError)) {
+      throw ex;
+    }
     message = ex.message;
     condition = false;
   }