At the moment the masking of bindings is solved by
specially named contexts, bindings and attributes.
This masking stuff must be filtered out in
api.Context, because it is implementation detail
which API clients should not know about.
Different proposal is to add explicit support for
masking into Registry SPI. If this gets
implemented the filtering in api.Context is not
This task should analyze both options and choose
one and then implement it.
Reassigning to new module owner jskrivanek.
Registry module is obsolete.