A random hash could potential have top 10 bits be non zero which would
pass the hash != PropertyArray::kNoHashSentinel test but fail the
masked_hash != PropertyArray::kNoHashSentinel.


Bug: v8:6404, chromium:757750
Change-Id: Iade531fefc75dd76bd7a89b377d17e59532087d8
Reviewed-on: https://chromium-review.googlesource.com/627380Reviewed-by: Adam Klein <adamk@chromium.org>
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#47528}