Debug infos for embedded builtins (associating a file and line number
with certain code ranges) should only be emitted in debug modes.

This CL disables source position emission in Torque in release builds,
and adds checks that the external filename / source position lists are
empty in release builds.

Bug: v8:9910
Change-Id: Ic69683a2324c3b334150ee2b7da9972fbee56483
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1879903Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64576}