Converts the Shape functions IsKey and IsLive to take ReadOnlyRoots
rather Isolate. This allows HashTableBase::FindEntry and
ObjectHashTableBase::Lookup to also take ReadOnlyRoots rather than
Isolate.

Bug: v8:7786
Change-Id: I37efea1d20139f394d6365569438755cb8fc44c4
Reviewed-on: https://chromium-review.googlesource.com/1133391Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Dan Elphick <delphick@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54390}