These aren't used thanks to new implementation in CSA.

BUG=v8:5977

Change-Id: Ia4acfa0d1a925eba305a818913cbeff479b27792
Reviewed-on: https://chromium-review.googlesource.com/458477
Commit-Queue: Peter Marshall <petermarshall@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#44151}