Some cleanup.
* bzrlib/tests/test_conflicts.py:
(TestResolveContentsConflict, TestResolvePathConflict): Cleanup
scenarios and sme method names.
* bzrlib/tests/test_conflicts.py:
(TestParametrizedResolveConflicts): Cleanup common parameter which
are really test class attributes.
* bzrlib/conflicts.py:
(PathConflict._infer_file_id): Cleaned up.