Specialize FindEntry for OrderedNameDictionary

Bug: v8:6443, v8:7569
Change-Id: I776415fde6bc2ea292b645fbca6952c7bb09d89d
Reviewed-on: https://chromium-review.googlesource.com/c/1329962Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#57431}