cmocka seems to #define fail to something inappropriate.
This is the first commit trying to unify csync_file_stat_s, csync_vio_file_stat_s and csync_tree_walk_file_s. Use QByteArray and unique_ptr already since I'm not used to track memory allocations and this will make the transition easier. Issue #1817
Just use cmocka_run_group_tests like we already use in some of those tests.