This moves all accesses from Typer to the broker. This is policed by
DisallowHandleDereferenceScope in Typer::Visitor::Reduce.

Bug: v8:7790
Change-Id: Ic37d029261b3302eedb902a3b2249834a5dd0512
Reviewed-on: https://chromium-review.googlesource.com/1095305
Commit-Queue: Jaroslav Sevcik <jarin@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53659}