Add a SetDoNotFragment() method to DatagramSocket, and call this for

content/browser/renderer_host/p2p/socket_host_udp_unittest.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 "content/browser/renderer_host/p2p/socket_host_udp.h"
 
 #include <stdint.h>
 #include <deque>
 #include <utility>
 #include <vector>
@@ skipping 97 matching lines @@
     scoped_refptr<net::IOBuffer> buffer(buf);
     std::vector<char> data_vector(buffer->data(), buffer->data() + buf_len);
     sent_packets_->push_back(UDPPacket(address, data_vector));
     return buf_len;
   }
 
   int SetReceiveBufferSize(int32_t size) override { return net::OK; }
 
   int SetSendBufferSize(int32_t size) override { return net::OK; }
 
+  int SetDoNotFragment() override { return net::OK; }
+
   void ReceivePacket(const net::IPEndPoint& address, std::vector<char> data) {
     if (!recv_callback_.is_null()) {
       int size = std::min(recv_size_, static_cast<int>(data.size()));
       memcpy(recv_buffer_->data(), &*data.begin(), size);
       *recv_address_ = address;
       net::CompletionCallback cb = recv_callback_;
       recv_callback_.Reset();
       recv_buffer_ = nullptr;
       cb.Run(size);
     } else {
@@ skipping 372 matching lines @@
   std::unique_ptr<P2PSocketHostUdp> socket_host(
       new P2PSocketHostUdp(&sender, 0, &throttler, fake_socket_factory));
   net::IPEndPoint local_address =
       ParseAddress(kTestLocalIpAddress, invalid_port);
   bool rv = socket_host->Init(local_address, min_port, max_port,
                               P2PHostAndIPEndPoint());
   EXPECT_FALSE(rv);
 }
 
 }  // namespace content