Split off from bug 747749. I'll do this once compartment-per-global lands. No particular reason why it depends on cpg, except that I want to avoid poking at this stuff right before the landing if I don't have to.
Created attachment 621312 [details] [diff] [review] Remove AutoPreserveCompartment. v1 Attaching a patch. Flagging luke for review.
Pushed this to try: https://tbpl.mozilla.org/?tree=Try&rev=985954fd006f
Looks green on try. Pushed to m-i: http://hg.mozilla.org/integration/mozilla-inbound/rev/b52e43bc204c