Revert "Fix: isSameIssue() should check counterparty"

[m3anid]

Reverts #836

[intelliot]

Why do you want to revert this commit?

[FredKSchott]

Just catching up here, was #835 introduced in the move to TypeScript? If #836 fixed one bug and introduced another (this issue?), there might be a missing or added call to renameCounterpartyToIssuer(). Hard to say without more info about what's broken here, but I remember changing issuer to counterparty for a reason.

[intelliot]

Good point. I'll take a closer look later today.

[intelliot]

We may want to move to using the term issuer instead of counterparty for consistency with rippled. Unfortunately, this is a departure from what RippleAPI has done in the past.

For instance, a USD obligation between A and B can equally be thought of as USD/A or USD/B. A having USD/B and B having USD/A is just the same number with an opposite sign. There is a USD balance between A and B and it can be positive or negative. So A and B can both be issuers on the XRP Ledger, as long we don't restrict "issuer" to only refer to someone who owes money to others.

I'm not sure if that completely clarifies things, but it does imply that issuer should be a fine term to use, as long as we expand what it means in our context. @mDuo13 what do you think?

[mDuo13]

That's about right. I mean, a lot of times we use "issuer" to mean the one who has a negative balance, so in that sense you can only be an "issuer" for a currency if others set nonzero trust limits to you for that currency. But, of course, rippled uses the "issuer" field to refer to either side of that relationship, as you described.

[intelliot]

We want to eventually move to using "issuer" in most contexts, but not for 1.0.0. Closing.