Add more ScriptForbiddenScope's

Lock down more things that updateRenderTree does so that they can't run
script. Some of these steps are called outside updateRenderTree too, so
having individual assert scopes makes sense even if updateRenderTree
itself never ran script.

Review URL: https://codereview.chromium.org/251903004

git-svn-id: svn://svn.chromium.org/blink/trunk@172827 bbb929c8-8fbe-4397-9dbb-9b2b20218538