canPlayType was undefined on <audio> and <video> elements. Adds HTMLMediaElement
extending Element with canPlayType returning values that match Chrome 145 on Linux
(probably/maybe/empty per MIME type). HTMLAudioElement and HTMLVideoElement extend
HTMLMediaElement. _elementClassFor routes AUDIO and VIDEO tags to the correct class.
Navigator: adds a global Navigator constructor so typeof Navigator !== 'undefined'.
Links it into the navigator prototype chain (_wdProto = Object.create(Navigator.prototype))
so navigator instanceof Navigator returns true, matching Chrome.
These are two of the signals in server-side fingerprint classifiers (fpCollect et al).
SGavrl
a7a7b0f4d8