Add a new QUIC platform API for text utilities.

net/quic/core/quic_versions.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/quic/core/quic_versions.h"
 
 #include "base/memory/ptr_util.h"
-#include "base/strings/string_number_conversions.h"
+#include "base/strings/string_piece.h"
 #include "net/quic/core/quic_error_codes.h"
 #include "net/quic/core/quic_flags.h"
 #include "net/quic/core/quic_tag.h"
 #include "net/quic/core/quic_types.h"
 
 using base::StringPiece;
 using std::string;
 
 namespace net {
 
@@ skipping 93 matching lines @@
   for (size_t i = 0; i < versions.size(); ++i) {
     if (i != 0) {
       result.append(",");
     }
     result.append(QuicVersionToString(versions[i]));
   }
   return result;
 }
 
 }  // namespace net