Merge branch 'va/git-p4-branch'

* va/git-p4-branch:
  t9801: do not overuse test_must_fail
  git-p4: Change p4 command invocation
  git-p4: Add test case for complex branch import
  git-p4: Search for parent commit on branch creation

diff --cc contrib/fast-import/git-p4
Simple merge