Before dropping a value we should validate that there is indeed a value
on the stack.

R=jkummerow@chromium.org

Bug: chromium:1184964
Change-Id: Iec3ac061df2545717749e664b10c383765d67c9d
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2739588Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73263}