This moves the initialization to JSArrayBuffer::SetupEmpty, which is the
proper bottleneck for all paths constructing array buffers.

Bug: chromium:1006600,v8:9380
Change-Id: I1887cb867627d69ade20654e5bc372b1ba1ac4e3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1815132Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63939}