Include operator<<() for StringPiece in libre2.so

operator<<() for StringPiece was moved under namespace re2 in an
earlier refactoring, but the exported symbols weren't updated with
the new mangled name.

Change-Id: If113a21d1ee136d06055e63ff89e486b73e07407
Reviewed-on: https://code-review.googlesource.com/29410
Reviewed-by: Paul Wankadia <junyer@google.com>

libre2.symbols

diff --git a/libre2.symbols b/libre2.symbols
index 1224baa..8308b64 100644
--- a/libre2.symbols
+++ b/libre2.symbols
@@ -6,8 +6,8 @@
 		# re2::StringPiece*
 		_ZN3re211StringPiece*;
 		_ZNK3re211StringPiece*;
-		# operator<<(std::ostream&, re2::StringPiece const&)
-		_ZlsRSoRKN3re211StringPieceE;
+		# re2::operator<<*
+		_ZN3re2ls*;
 		# re2::FilteredRE2*
 		_ZN3re211FilteredRE2*;
 		_ZNK3re211FilteredRE2*;

libre2.symbols.darwin

diff --git a/libre2.symbols.darwin b/libre2.symbols.darwin
index a4d942f..31e8c52 100644
--- a/libre2.symbols.darwin
+++ b/libre2.symbols.darwin
@@ -5,13 +5,8 @@
 # re2::StringPiece*
 __ZN3re211StringPiece*
 __ZNK3re211StringPiece*
-# operator<<(std::ostream&, re2::StringPiece const&)
-# Seen with libstdc++ on 10.8 and below:
-# __ZlsRSoRKN3re211StringPieceE
-# Seen with libc++ on 10.9 and above:
-# __ZlsRNSt3__113basic_ostreamIcNS_11char_traitsIcEEEERKN3re211StringPieceE
-# Note that "ls" means operator<<, so this is not overly broad.
-__Zls*RKN3re211StringPieceE
+# re2::operator<<*
+__ZN3re2ls*
 # re2::FilteredRE2*
 __ZN3re211FilteredRE2*
 __ZNK3re211FilteredRE2*