'Gets the video player dimensions.
Returns:
tuple: Dimensions'

@property
def _dimensions(self):

    iframe_selector = self.get_element_selector('.video-player    iframe,')
    video_selector = self.get_element_selector('    .video-player    video')
    video = self._get_element_dimensions((iframe_selector + video_selector))
    wrapper = self._get_element_dimensions(self.get_element_selector('.tc-wrapper'))
    controls = self._get_element_dimensions(self.get_element_selector('.video-controls'))
    progress_slider = self._get_element_dimensions(self.get_element_selector('.video-controls    >    .slider'))
    expected = dict(wrapper)
    expected['height'] -= (controls['height'] + (0.5 * progress_slider['height']))
    return (video, expected)
