Refactor|libcommon|SaveSlots: Eliminate API for reverse SaveSlot lookup by SavedSession
SaveSlots should support reverse lookup of a save slot by SavedSession pointer/address as this confuses the design of this component. The API now fully encapsulates save slot -> saved session binding and does not make public the details of the internal linkage mechanism.
Refactor|libcommon|SaveSlots: Eliminate API for reverse SaveSlot lookup by SavedSession
SaveSlots should support reverse lookup of a save slot by SavedSession
pointer/address as this confuses the design of this component. The API
now fully encapsulates save slot -> saved session binding and does not
make public the details of the internal linkage mechanism.