This stopped working because of r47337 (
https://chromium-review.googlesource.com/c/v8/v8/+/605949/8/src/compiler.cc#418
).

Also enhanced the test so that it would've caught this.

BUG=v8:5516

Change-Id: I933a8b5d787c3eb8b2cc230e2b35df1f25b500e7
Reviewed-on: https://chromium-review.googlesource.com/625618Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Commit-Queue: Marja Hölttä <marja@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47498}