but origin_visit_add() which requires more work to do so.
Note that this will change the way 'raw_extrinsinc_metadata_add()'
report statsd metrics: the 'method_name' tag will now remain
'raw_extrinsic_metadata_add' instead of a forged '<type_name>_metadata_add'.
Also properly annotate output of Storage.xxx_add() methods as Dict[str, int]
when applicable.
This is especially needed to be able to help writing consistent proxy storages
(like the buffer of the tenacious one) and have them properly handly all
_add methods the same. For example, the buffer storage is currently only
dealing with "core" object types, and extending id to other object types
is not as straighforward as it should be.