simplemerge: make minimize() a free function
IMO, `Merge3Text` should be about merging text without knowing about
conflict markers. "Conflict minimization" is about making conflict
markers smaller, so it should be moved out. This patch does that. I'll
refactor it next.
Differential Revision: https://phab.mercurial-scm.org/D11980
$ hg init
$ touch a
$ unset HGUSER
$ echo "[ui]" >> .hg/hgrc
$ echo "username= foo" >> .hg/hgrc
$ echo " bar1" >> .hg/hgrc
$ hg ci -Am m
adding a
abort: username 'foo\nbar1' contains a newline
[255]
$ rm .hg/hgrc
$ HGUSER=`(echo foo; echo bar2)` hg ci -Am m
adding a
abort: username 'foo\nbar2' contains a newline
[255]
$ hg ci -Am m -u "`(echo foo; echo bar3)`"
adding a
transaction abort!
rollback completed
abort: username 'foo\nbar3' contains a newline
[50]