animation-test-helper.js has this: var hasPauseAnimationAPI = window.layoutTestController && layoutTestController.pauseAnimationAtTimeOnElementWithId; That expression does not evaluate to boolean; hasPauseAnimationAPI is 'undefined' if the API is not present. A better form is: var hasPauseAnimationAPI = ('layoutTestController' in window) && ('pauseAnimationAtTimeOnElementWithId' in layoutTestController);
Same issue in transition-test-helpers.js
Sending LayoutTests/ChangeLog Sending LayoutTests/animations/animation-test-helpers.js Sending LayoutTests/transitions/transition-test-helpers.js Transmitting file data ... Committed revision 39687.