successful write.
* fhandler.h (fhandler_base::status_flags): Add 'has_changed' flag.
* fhandler_disk_file.cc (fhandler_disk_file::fchmod): Call
fhandler_disk_file's own open and close instead of open_fs and
close_fs. Mark as changed on success.
(fhandler_disk_file::fchown): Ditto.
(fhandler_disk_file::facl): Ditto.
(fhandler_disk_file::ftruncate): Ditto.
(fhandler_base::open_fs): Mark as changed when O_TRUNC flag on existing
file is set.
(fhandler_disk_file::close): Set st_ctime if has_changed flag is set.
8be730bbb1