Add SpdyString alias for std::string in net/spdy.

net/spdy/spdy_alt_svc_wire_format.h

 // Copyright (c) 2015 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.
 
 // This file contains data structures and utility functions used for serializing
 // and parsing alternative service header values, common to HTTP/1.1 header
 // fields and HTTP/2 and QUIC ALTSVC frames.  See specification at
 // https://httpwg.github.io/http-extensions/alt-svc.html.
 
 #ifndef NET_SPDY_SPDY_ALT_SVC_WIRE_FORMAT_H_
 #define NET_SPDY_SPDY_ALT_SVC_WIRE_FORMAT_H_
 
-#include <stdint.h>
-
+#include <cstdint>
 #include <vector>
 
 #include "net/base/net_export.h"
+#include "net/spdy/platform/api/spdy_string.h"
 #include "net/spdy/platform/api/spdy_string_piece.h"
 
 namespace net {
 
 namespace test {
 class SpdyAltSvcWireFormatPeer;
 }  // namespace test
 
 class NET_EXPORT_PRIVATE SpdyAltSvcWireFormat {
  public:
   using VersionVector = std::vector<uint16_t>;
 
   struct NET_EXPORT_PRIVATE AlternativeService {
-    std::string protocol_id;
-    std::string host;
+    SpdyString protocol_id;
+    SpdyString host;
 
     // Default is 0: invalid port.
     uint16_t port = 0;
     // Default is one day.
     uint32_t max_age = 86400;
     // Default is empty: unspecified version.
     VersionVector version;
 
     AlternativeService();
-    AlternativeService(const std::string& protocol_id,
-                       const std::string& host,
+    AlternativeService(const SpdyString& protocol_id,
+                       const SpdyString& host,
                        uint16_t port,
                        uint32_t max_age,
                        VersionVector version);
     AlternativeService(const AlternativeService& other);
     ~AlternativeService();
 
     bool operator==(const AlternativeService& other) const {
       return protocol_id == other.protocol_id && host == other.host &&
              port == other.port && version == other.version &&
              max_age == other.max_age;
     }
   };
   // An empty vector means alternative services should be cleared for given
   // origin.  Note that the wire format for this is the string "clear", not an
   // empty value (which is invalid).
   typedef std::vector<AlternativeService> AlternativeServiceVector;
 
   friend class test::SpdyAltSvcWireFormatPeer;
   static bool ParseHeaderFieldValue(SpdyStringPiece value,
                                     AlternativeServiceVector* altsvc_vector);
-  static std::string SerializeHeaderFieldValue(
+  static SpdyString SerializeHeaderFieldValue(
       const AlternativeServiceVector& altsvc_vector);
 
  private:
   static void SkipWhiteSpace(SpdyStringPiece::const_iterator* c,
                              SpdyStringPiece::const_iterator end);
   static bool PercentDecode(SpdyStringPiece::const_iterator c,
                             SpdyStringPiece::const_iterator end,
-                            std::string* output);
+                            SpdyString* output);
   static bool ParseAltAuthority(SpdyStringPiece::const_iterator c,
                                 SpdyStringPiece::const_iterator end,
-                                std::string* host,
+                                SpdyString* host,
                                 uint16_t* port);
   static bool ParsePositiveInteger16(SpdyStringPiece::const_iterator c,
                                      SpdyStringPiece::const_iterator end,
                                      uint16_t* value);
   static bool ParsePositiveInteger32(SpdyStringPiece::const_iterator c,
                                      SpdyStringPiece::const_iterator end,
                                      uint32_t* value);
 };
 
 }  // namespace net
 
 #endif  // NET_SPDY_SPDY_ALT_SVC_WIRE_FORMAT_H_