This removes the ability to create a copy of a code-stub with a given
replacement pattern applied. It is in preparation of having the ability
to write-protect code objects.

R=ishell@chromium.org
BUG=v8:6409

Change-Id: Id7528b3bfc53ece73d8c58b0ac96c6e5702a9d45
Reviewed-on: https://chromium-review.googlesource.com/654605Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47914}