Fix parsing of Mercurial git diffs that add binary files.
Review Request #14071 — Created Aug. 2, 2024 and submitted — Latest diff uploaded
A previous fix had added overrides for binary files in Mercurial-
generated git diffs to fix up the commit IDs, because those
did not include an index line. Unfortunately, added binary files in
Mercurial git diffs do include an index line, and the override was
stomping on the PRE_CREATION orig version. This change fixes that up.
Ran unit tests. New test failed before the fix and succeeds after.