`deletion_time` is a part of the `partition_header`, which is in turn
a part of `partition`. and `data_file` is a sequence of `partition`.
`data_file` represents *-Data.db component of an SSTable.
see docs/architecture/sstable3/sstables-3-data-file-format.rst.
we always parse the data component via `flat_mutation_reader_v2`, which is in turn
implemented with mx/reader.cc or kl/reader.cc depending on
the version of SSTable to be read.
in other words, we decode `deletion_time` in mx/reader.cc or
kl/reader.cc, not in sstable.cc. so let's drop the overload
parse() for deletion_time. it's not necessary and more importantly,
confusing.
Refs #15116
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#15756
c8cb70918b