This reverts commit 88376a78.

Reason for revert: the number of buckets could change, so we can't cache the value

Original change's description:
> [OrderedHashSet] Remove redundant hash to bucket
> 
> Bug: v8:5717
> Change-Id: I88e1e3089844b0955f0f7a6a792c2e10949a5b18
> Reviewed-on: https://chromium-review.googlesource.com/480927
> Reviewed-by: Adam Klein <adamk@chromium.org>
> Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#44707}

TBR=adamk@chromium.org,cbruni@chromium.org,gsathya@chromium.org,v8-reviews@googlegroups.com
# Not skipping CQ checks because original CL landed > 1 day ago.

Change-Id: I4d42021a1d1f5bc069b3787efc828761098038e0
Reviewed-on: https://chromium-review.googlesource.com/483903Reviewed-by: Sathya Gunasekaran <gsathya@chromium.org>
Reviewed-by: Adam Klein <adamk@chromium.org>
Commit-Queue: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#44760}