In a new test suite: "wasm-api-tests", using a new binary "wasm_api_tests",
powered by gtest/gmock (like unittests).
Also fix a bunch of issues that these tests uncovered, mostly to ensure
that the stack is walkable.

Change-Id: I1d5604eea85da078ebecd4ebb7383647595f16ac
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1627539
Commit-Queue: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Michael Starzinger <mstarzinger@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61885}