With exception handling enabled new call paths open up, which will
perform environment merging while a "call" or "call_indirect" is
currently being emitted. This will lead to double-use of the buffer
returned by calls to {Buffer} or {Realloc}. In general we should
transition away from this optimization to safer constructs such as
{base::SmallVector} to avoid such bugs.

R=clemensb@chromium.org
TEST=mjsunit/regress/regress-9832
BUG=v8:9832

Change-Id: I4c862ac1bc7dc34ad62279c82f6414153e8cbddb
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1856006
Commit-Queue: Michael Starzinger <mstarzinger@chromium.org>
Reviewed-by: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64271}