This was originally a flag for debugging the compilation of a module
by skipping compilation of the first N functions in a module. This
flag is not properly respected anymore, and is an unnecessary complication.

R=herhut@chromium.org

Change-Id: If9bf80245f6982a8383ca3865c599d58319feba9
Reviewed-on: https://chromium-review.googlesource.com/1061468Reviewed-by: Stephan Herhut <herhut@chromium.org>
Commit-Queue: Ben Titzer <titzer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53365}