We made array-concat run faster in https://crrev.com/c/2504853.

Bug: v8:7783
Change-Id: Iabefb58f92e24ffa4e0589a7c8b9e2b3e12c6e47
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2504859
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Reviewed-by: Santiago Aboy Solanes <solanes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#70831}