Don't try to match "key" when not using sqlcipher. (#752, #753) r=nalexander
Don't try to match "key" when not using sqlcipher. (#752, #753) r=nalexander

This causes a runtime error, since `opt_str("key")` isn't recognized.
ncalexan/mentat,mozilla/mentat,mozilla/mentat,ncalexan/mentat,mozilla/mentat,ncalexan/datomish,ncalexan/datomish,ncalexan/mentat,mozilla/mentat,ncalexan/mentat,mozilla/mentat,mozilla/mentat,ncalexan/mentat,ncalexan/mentat