Revert of [wasm] include JS conformance tests in Wasm mjsunit tests (patchset #5 id:80001 of https://codereview.chromium.org/2660903003/ )

Reason for revert:
http://crbug.com/687279

Original issue's description:
> [wasm] include JS conformance tests in Wasm mjsunit tests
>
> BUG=
>
> Review-Url: https://codereview.chromium.org/2660903003
> Cr-Commit-Position: refs/heads/master@{#42821}
> Committed: https://chromium.googlesource.com/v8/v8/+/eb9b5edffb8c5acb0abdff0729901f95dbd3ccac

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

Review-Url: https://codereview.chromium.org/2663063005
Cr-Commit-Position: refs/heads/master@{#42823}