net: Update the include paths of base/string_piece.h to its new location.

net/quic/quic_fec_group.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.
 //
 // Tracks information about an FEC group, including the packets
 // that have been seen, and the running parity.  Provided the ability
 // to revive a dropped packet.
 
 #ifndef NET_QUIC_QUIC_FEC_GROUP_H_
 #define NET_QUIC_QUIC_FEC_GROUP_H_
 
 #include <set>
 
-#include "base/string_piece.h"
+#include "base/strings/string_piece.h"
 #include "net/quic/quic_protocol.h"
 
 namespace net {
 
 class NET_EXPORT_PRIVATE QuicFecGroup {
  public:
   QuicFecGroup();
   ~QuicFecGroup();
 
   // Updates the FEC group based on the delivery of a data packet.
@@ skipping 63 matching lines @@
   char payload_parity_[kMaxPacketSize];
   size_t payload_parity_len_;
   bool entropy_parity_;
 
   DISALLOW_COPY_AND_ASSIGN(QuicFecGroup);
 };
 
 }  // namespace net
 
 #endif  // NET_QUIC_QUIC_FEC_GROUP_H_