When I/O error (e.g. EMFILE / ENOSPC) happens we hit
an assert in ~append_challenged_posix_file_impl(): Assertion _closing_state == state::closed' failed.
Commit 6160b9017d add close on failure
of the lamda defined in allocate_segment_ex, but it doesn't handle an error
after the file is opened/created while it is wrapped with commitlog_file_extensions.
Refs #5657
Signed-off-by: Benny Halevy <bhalevy@scylladb.com>
Reviewed-by: Calle Wilund <calle@scylladb.com>
Message-Id: <20200414115231.298632-1-bhalevy@scylladb.com>
(cherry picked from commit 35892e4557)