branch heads: fix regression introduced in
e67e5b60e55f (
issue1726)
For merge nodes it is not adequate to only check a single possible
branch head for whether it is an ancestor of the latest head, but it
needs to be done for each possible branch head.
adding he
llo
abort: '\n' and '\r' disallowed in filenames: 'he\rllo'
adding he
llo
abort: '\n' and '\r' disallowed in filenames: 'he\rllo'
adding hell
o
abort: '\n' and '\r' disallowed in filenames: 'hell\no'
adding hell
o
abort: '\n' and '\r' disallowed in filenames: 'hell\no'
f he
llo he
llo
f hell
o hell
o