Revert "Observe document: some client scripts might change documentElement"
Revert "Observe document: some client scripts might change documentElement"

This reverts commit 2276a1532680ae4e695085f0cded1993b53721fa.

kapouer/node-webkitgtk,kapouer/node-webkitgtk,kapouer/node-webkitgtk,kapouer/node-webkitgtk