kgb's signature compatibility is getting more strict, and we have a few

functions passed in that don't match the signatures for the original

functions. We also have a direct assignment for a variable to reset the

calls on a spy, which wasn't correct.
This change fixes both by using the proper variable names for the

function being overridden and calling reset_calls() to reset the call

state.

Unit tests pass with the new kgb and old kgb.