Fix size_t truncations in net for 64-bit VS 2015

net/socket/socks5_client_socket_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 "net/socket/socks5_client_socket.h"
 
 #include <algorithm>
 #include <iterator>
 #include <map>
 
@@ skipping 176 matching lines @@
 TEST_F(SOCKS5ClientSocketTest, ConnectAndDisconnectTwice) {
   const std::string hostname = "my-host-name";
   const char kSOCKS5DomainRequest[] = {
       0x05,  // VER
       0x01,  // CMD
       0x00,  // RSV
       0x03,  // ATYPE
   };
 
   std::string request(kSOCKS5DomainRequest, arraysize(kSOCKS5DomainRequest));
-  request.push_back(hostname.size());
+  request.push_back(static_cast<char>(hostname.size()));
   request.append(hostname);
   request.append(reinterpret_cast<const char*>(&kNwPort), sizeof(kNwPort));
 
   for (int i = 0; i < 2; ++i) {
     MockWrite data_writes[] = {
         MockWrite(SYNCHRONOUS, kSOCKS5GreetRequest, kSOCKS5GreetRequestLength),
         MockWrite(SYNCHRONOUS, request.data(), request.size())
     };
     MockRead data_reads[] = {
         MockRead(SYNCHRONOUS, kSOCKS5GreetResponse, kSOCKS5GreetResponseLength),
@@ skipping 164 matching lines @@
     EXPECT_TRUE(user_sock_->IsConnected());
     net_log_.GetEntries(&net_log_entries);
     EXPECT_TRUE(LogContainsEndEvent(net_log_entries, -1,
                                     NetLog::TYPE_SOCKS5_CONNECT));
   }
 }
 
 }  // namespace
 
 }  // namespace net