[D-runtime] TypeInfo_Invariant -> …_Immutable?

[David Nadlinger]

Hi all,

I'd like to change the name of TypeInfo_Invariant, the wrapper for
adding a layer of 'immutable' to a type, to TypeInfo_Immutable, as it
makes things clearer when working on the DMD/druntime internals –
especially to newcomers, as invariant had its current meaning for ages
now.

Am I missing a way this could actually break client code (on the API
level, the ABI obviously changes, but we do that all the time)?
TypeInfo_Invariant is in object, but not documented.

David