[whatwg] allowfullscreen vs sandbox="allow-fullscreen", and mimicking for pointer lock

[Vincent Scheib]

I'm currently implementing Pointer Lock [1] in WebKit, which was adjusted
recently to mimic Fullscreen [2].

Why does the Fullscreen specification use an iframe attribute
allowfullscreen to permit/restrict iframe capabilities instead of using
iframe sandbox="allow-fullscreen"?

[1] http://dvcs.w3.org/hg/pointerlock/raw-file/default/index.html
[2] http://dvcs.w3.org/hg/fullscreen/raw-file/tip/Overview.html