Allow any media-containing frame to correctly reset. Fix LEI-93, an issue where the second of two consecutive videos did not play correctly.

Due to an internal ember quirk/optimization, the component instance is not destroyed if two of the same thing are used in a row, which means the same video tag was being dynamically reassigned- something HTML does not normally allow. The page needs to be manually told to load the correct new video.

See commentary here: http://stackoverflow.com/a/18454389/1422268