Fix header guards in //net.

net/quic/chromium/mock_quic_data.h

 // Copyright 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.
 
+#ifndef NET_QUIC_CHROMIUM_MOCK_QUIC_DATA_H_
+#define NET_QUIC_CHROMIUM_MOCK_QUIC_DATA_H_
+
 #include "net/quic/core/quic_packets.h"
 #include "net/socket/socket_test_util.h"
 
 namespace net {
 namespace test {
 
 // Helper class to encapsulate MockReads and MockWrites for QUIC.
 // Simplify ownership issues and the interaction with the MockSocketFactory.
 class MockQuicData {
  public:
@@ skipping 40 matching lines @@
   std::vector<std::unique_ptr<QuicEncryptedPacket>> packets_;
   std::unique_ptr<MockConnect> connect_;
   std::vector<MockWrite> writes_;
   std::vector<MockRead> reads_;
   size_t sequence_number_;
   std::unique_ptr<SequencedSocketData> socket_data_;
 };
 
 }  // namespace test
 }  // namespace net
+
+#endif  // NET_QUIC_CHROMIUM_MOCK_QUIC_DATA_H_