8 EXPECTED (panel = mediaControlsElement(shadowRoot.firstChild, '-webkit-media-controls-panel') != 'null') OK
9 EXPECTED (internals.shadowPseudoId(panel) == '-webkit-media-controls-panel') OK
10 EXPECTED (document.defaultView.getComputedStyle(panel)['display'] != 'none') OK
11 EXPECTED (document.defaultView.getComputedStyle(panel)['height'] >= '20px') OK
8EXPECTED (panel = mediaControlsElement(shadowRoot.firstChild, '-webkit-media-controls-panel') != 'null'), OBSERVED 'null' FAIL
9TypeError: Argument 1 ('element') to Internals.shadowPseudoId must be an instance of Element
10TypeError: Type error
11TypeError: Type error