Always use NonBlocking IO for UDP sockets on Windows.

net/socket/fuzzed_datagram_client_socket.cc

 // Copyright 2016 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 "net/socket/fuzzed_datagram_client_socket.h"
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/location.h"
@@ skipping 68 matching lines @@
   return OK;
 }
 
 int FuzzedDatagramClientSocket::GetLocalAddress(IPEndPoint* address) const {
   if (!connected_)
     return ERR_SOCKET_NOT_CONNECTED;
   *address = IPEndPoint(IPAddress(1, 2, 3, 4), 43210);
   return OK;
 }
 
-void FuzzedDatagramClientSocket::UseNonBlockingIO() {}
-
 const NetLogWithSource& FuzzedDatagramClientSocket::NetLog() const {
   return net_log_;
 }
 
 int FuzzedDatagramClientSocket::Read(IOBuffer* buf,
                                      int buf_len,
                                      const CompletionCallback& callback) {
   CHECK(!callback.is_null());
   CHECK_GT(buf_len, 0);
   CHECK(!read_pending_);
@@ skipping 86 matching lines @@
     const net::CompletionCallback& callback,
     int result) {
   CHECK(connected_);
   CHECK(write_pending_);
 
   write_pending_ = false;
   callback.Run(result);
 }
 
 }  // namespace net