Only match addresses without zip codes if at the end.

The old native implementation of findAddress only accepted addresses
without zip codes if they appeared at the end of the string. This was
probably a bug as the documentation implies this should work in all
cases, but fixing this bug has caused a lot of false positives while not
fixing very many false negatives and this functionality is being
deprecated anyway, so change it back.

Fixes: 75409267
Test: tested upstream in chromium; direct copy of that code
Change-Id: I3f3c300035cf02a23284737431bc6f94f542cbe7