Adding test to confirm that no one-shot optimizations are not done
for functions enclosed in parentheses but not immediately invoked
in an assignment.

Bug: v8:8072
Change-Id: I282132a7cc570b59290f2ec314462be060d48e5a
Reviewed-on: https://chromium-review.googlesource.com/c/1238576
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56763}