Revert of [wasm] Turn on trap-if by default. (patchset #1 id:1 of https://codereview.chromium.org/2647323002/ )

Reason for revert:
gc-stress failures

Original issue's description:
> [wasm] Turn on trap-if by default.
>
> This CL turns on trap-if by default, and it changes the tests so that
> traps in the cctests are also tested without trap-if.
>
> R=titzer@chromium.org, clemensh@chromium.org, bradnelson@chromium.org
>
> Review-Url: https://codereview.chromium.org/2647323002
> Cr-Commit-Position: refs/heads/master@{#42603}
> Committed: https://chromium.googlesource.com/v8/v8/+/01c87ebe70fb569205432597f3105c708bba0fef

TBR=bradnelson@chromium.org,titzer@chromium.org,ahaas@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review-Url: https://codereview.chromium.org/2645403005
Cr-Commit-Position: refs/heads/master@{#42604}