This ensure that once features are added for other platform, we don't
forget to implement all platform specific methods that are then being
used.

R=ahaas@chromium.org

Bug: v8:6600
Change-Id: I4cc948da280fdb63da1938edc6b391d180b88cad
Reviewed-on: https://chromium-review.googlesource.com/853494
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50401}