diff --git a/browser/components/loop/test/shared/loop_mocha_utils.js b/browser/components/loop/test/shared/loop_mocha_utils.js
index 54df304b572..800d9e9cda7 100644
--- a/browser/components/loop/test/shared/loop_mocha_utils.js
+++ b/browser/components/loop/test/shared/loop_mocha_utils.js
@@ -64,6 +64,8 @@ var LoopMochaUtils = (function(global, _) {
       throw result;
     };
 
+    this.catch = function() {};
+
     asyncFn(this.resolve.bind(this), this.reject.bind(this));
   }