Backed out changeset d7d447cac91b (bug 969762) for tp5 regression.
Bug 969728 - Make users using temporary profile possible to update using the maintenance service. r=bbondy
Bug 970483 - Part 1: Introduce IsWindowsBuildOrLater() and IsWin7RTMOrLater(). r=bbondy
Bug 970483 - Part 2: Blackliist pre-RTM Windows 7 again. r=jfkthame