[wasm] update js-api test runner and expectations

wasm-module-builder:
- consistently adds the end opcode in function
bodies (using addBody).
- add missing setTableLength method

table/get-set:
- Avoid unrelated errors like: Cannot destructure
property `fn` of 'undefined' or 'null'.

Bug: 926311, v8:8319
Change-Id: Ia7db1ee5c3a9b1c1d6092cdce8885ddee4dd9b0e
Reviewed-on: https://chromium-review.googlesource.com/c/1458099
Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Sven Sauleau <ssauleau@igalia.com>
Cr-Commit-Position: refs/heads/master@{#633121}
23 files changed