The current processing of a transition array is not safe because the
targets in the array have conditional weakness, which can change
concurrently.

Bug: chromium:694255
Change-Id: I86bf7151af39307dc4101a0b0ca02ef7c704df53
Reviewed-on: https://chromium-review.googlesource.com/641410Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47682}