This CL makes the TypedArray#sort unit test more robust, that checks
for the stable property.

R=jgruber@chromium.org

Bug: v8:8567
Change-Id: I8e6a729d0a8b54901535d49eb578b8b34bd6f2eb
Reviewed-on: https://chromium-review.googlesource.com/c/1449695Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Mathias Bynens <mathias@chromium.org>
Commit-Queue: Simon Zünd <szuend@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59316}