Add QuicStringPiece which is actually StringPiece.

net/quic/core/quic_session.h

 // 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.
 //
 // A QuicSession, which demuxes a single connection to individual streams.
 
 #ifndef NET_QUIC_CORE_QUIC_SESSION_H_
 #define NET_QUIC_CORE_QUIC_SESSION_H_
 
 #include <cstddef>
 #include <map>
 #include <memory>
 #include <string>
 #include <unordered_set>
 #include <vector>
 
 #include "base/compiler_specific.h"
 #include "base/macros.h"
-#include "base/strings/string_piece.h"
 #include "net/quic/core/quic_connection.h"
 #include "net/quic/core/quic_crypto_stream.h"
 #include "net/quic/core/quic_packet_creator.h"
 #include "net/quic/core/quic_packets.h"
 #include "net/quic/core/quic_stream.h"
 #include "net/quic/core/quic_write_blocked_list.h"
 #include "net/quic/platform/api/quic_containers.h"
 #include "net/quic/platform/api/quic_export.h"
 #include "net/quic/platform/api/quic_socket_address.h"
 
@@ skipping 411 matching lines @@
 
   // Latched value of gfe2_reloadable_flag_quic_flow_control_invariant.
   const bool flow_control_invariant_;
 
   DISALLOW_COPY_AND_ASSIGN(QuicSession);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_CORE_QUIC_SESSION_H_