tests/test-manifest-merging.t

largefiles: centralize the logic to get outgoing largefiles

Before this patch, "overrides.getoutgoinglfiles()" (called by
"overrideoutgoing()" and "overridesummary()") and "lfilesrepo.push()"
implement similar logic to get outgoing largefiles separately.

This patch centralizes the logic to get outgoing largefiles in
"lfutil.getlfilestoupload()".

"lfutil.getlfilestoupload()" takes "addfunc" argument, because each
callers need different information (and it is useful for enhancement
in the future).

  - "overrides.getoutgoinglfiles()" needs only filenames
  - "lfilesrepo.push()" needs only hashes of largefiles

  $ hg init base

  $ cd base
  $ echo 'alpha' > alpha
  $ hg ci -A -m 'add alpha'
  adding alpha
  $ cd ..

  $ hg clone base work
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ cd work
  $ echo 'beta' > beta
  $ hg ci -A -m 'add beta'
  adding beta
  $ cd ..

  $ cd base
  $ echo 'gamma' > gamma
  $ hg ci -A -m 'add gamma'
  adding gamma
  $ cd ..

  $ cd work
  $ hg pull -q
  $ hg merge
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)

Update --clean to revision 1 to simulate a failed merge:

  $ rm alpha beta gamma
  $ hg update --clean 1
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ cd ..