Module and script SharedFunctionInfos can't be used interchangeably
(e.g.: it should not be possible to bind a Module's SFI to a Context).

The dedicated type disambiguates the two.

This also adds an overload for CreateCodeCache which takes an unbound
module script instead of an unbound script. Both are just a SFI
underneath, so their behavior is identical.

Bug: v8:7685
Cq-Include-Trybots: luci.chromium.try:linux_chromium_rel_ng
Change-Id: Iab519d0d50b6b41c95abdb6397f5622e292da4d8
Reviewed-on: https://chromium-review.googlesource.com/1047107
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53150}