Removes JS version and creates a runtime functions for now to
interface with existing JS uses.

Bug: v8:5751
Cq-Include-Trybots: luci.v8.try:v8_linux_noi18n_rel_ng
Change-Id: I150701d338a0951a5e5da1aca667c65f941850d9
Reviewed-on: https://chromium-review.googlesource.com/1122024
Commit-Queue: Sathya Gunasekaran <gsathya@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54145}