Do not rewrite base_commit_id if not necessary
Review Request #11145 — Created Aug. 20, 2020 and submitted — Latest diff uploaded
If the base_commit_id does not contains any relative information we do not need to rewrite it. This saves one another call of hg binary.
Used a base_commit_id with relative character and saw
the rewrite. Used a normal base_commit_id and saw
that it did not rewrite.