dfa4ed19bb
Fix intermediate vpub_new leakage in multi joinsplit tx Resolves information leakage discussed here https://github.com/zcash/zcash/issues/1360#issuecomment-284561331 Example output in debug.log showing how intermediate vpub_new is now 0 https://gist.github.com/bitcartel/86ca316b74f0b1ec6d8de3ac132006da When reviewing, note that the indentation of a large chunk of code (scenario 3 part 2) changed, so use `git diff -w` (or similar) or append `?w=1` to the Github URL e.g. https://github.com/zcash/zcash/pull/2440/files?w=1