Remove EncodeDestination's overload relying on global state

Summary:
This makes access to global state explicit, which is a good step toward eliminating it.

Depends on D3536, D3543 and D3549

Test Plan:

make check

Reviewers: #bitcoin_abc, markblundeberg

Reviewed By: #bitcoin_abc, markblundeberg

Differential Revision: https://reviews.bitcoinabc.org/D3550