OpParameter<int32_t> was still used for an operator after the operators
parameter changed from int32_t to a struct. Coincidentally, the first
field of the struct holds the value previously stored in that int32_t,
so correctness tests did not catch this.

Bug: chromium:818611, v8:7517
Change-Id: Ie46f084f7fa8117cd3493fc5ceafac11553dc55e
Reviewed-on: https://chromium-review.googlesource.com/948546
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51728}