Direct call to CloneFastJSArray is used to improve performance in that
case. Tests are also added.
Bug: v8:7980
Change-Id: Ifca34f3e182b776cd9862da8bf529fc13f6be9ed
Reviewed-on: https://chromium-review.googlesource.com/1172782
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Commit-Queue: Hai Dang <dhai@google.com>
Cr-Commit-Position: refs/heads/master@{#55154}
