--- a/dom/vr/test/mochitest/VRSimulationDriver.js
+++ b/dom/vr/test/mochitest/VRSimulationDriver.js
@@ -3,17 +3,16 @@ var VRServiceTest;
 var vrMockDisplay;
 
 var VRSimulationDriver = (function() {
 "use strict";
 
 var AttachWebVRDisplay = function() {
   var promise = VRServiceTest.attachVRDisplay("VRDisplayTest");
   promise.then(function (display) {
-    assert_true(display != null, "AttachWebVRDisplay should success.");
     vrMockDisplay = display;
   });
 
   return promise;
 };
 
 var SetVRDisplayPose = function(position,
                                 linearVelocity, linearAcceleration,