A MediaDocument on iOS can't rely on the intrinsic size of the content, since it does not load the content. Also, you really want the element to fill the page. <rdar://problem/16510042>
Created attachment 229497 [details] Patch
Comment on attachment 229497 [details] Patch r=me
Committed r167402: <http://trac.webkit.org/changeset/167402>