tree 94c377d74fe1f606104dc957cf70cb6b4d2cbfa9
parent bc5d6ae59f2bf8fa887e1fa6b00e8662d5953d86
author Paul Wankadia <junyer@google.com> 1552895372 -0700
committer Paul Wankadia <junyer@google.com> 1552895501 +0000

Get rid of `using std::string;`. (part 2 of N)

Change-Id: I3451b06b238ad93eefc1e2b387351ec6f0ff792d
Reviewed-on: https://code-review.googlesource.com/c/re2/+/39112
Reviewed-by: Paul Wankadia <junyer@google.com>