Makes the declaration slice resolve lazely when using `@typeInfo`

This way all the declarations in a container won't be resolved untill
the user actually uses the decls slice in the builtin TypeInfo union.
7560fc716dTimon Kruiper committed on 2/18/2020, 8:26:37 PM· committed by Andrew Kelleyparente8a8492
4 files changedLine totals unavailable