StoreKey and Querier Key Usage Ambiguous

[jackzampolin]

There are may spots in the SDK where store key is passed in as an argument. This can (and in many situations seems to) lead to hard coded strings with the store keys being used (CLI has a number of examples of this). If left unchecked this will cause issues with inconsistencies if we ever decide to rename any of the stores. I don't know the best way forward here, but would love some thoughts on how to fix this.

One example https://github.com/cosmos/cosmos-sdk/blob/develop/client/lcd/root.go#L167

cc @alexanderbez

[alexanderbez]

Yeah, I do think they should live as constants somewhere. Thing we have to be careful of is still abiding by the object capability model and not allowing for arbitrary modules/keepers to get access to stores they shouldn't be getting access to.

[jackzampolin]

This is addressed by #3119