Make CertVerifier a pure virtual interface.

net/socket/ssl_client_socket_mac.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/ssl_client_socket_mac.h"
 
 #include <CoreServices/CoreServices.h>
 #include <netdb.h>
 #include <sys/socket.h>
 #include <sys/types.h>
 
 #include <algorithm>
 
 #include "base/bind.h"
 #include "base/lazy_instance.h"
 #include "base/mac/mac_logging.h"
 #include "base/mac/scoped_cftyperef.h"
 #include "base/string_util.h"
 #include "net/base/address_list.h"
 #include "net/base/cert_verifier.h"
 #include "net/base/io_buffer.h"
 #include "net/base/net_errors.h"
 #include "net/base/net_log.h"
+#include "net/base/single_request_cert_verifier.h"
 #include "net/base/ssl_cert_request_info.h"
 #include "net/base/ssl_connection_status_flags.h"
 #include "net/base/ssl_info.h"
 #include "net/base/x509_certificate_net_log_param.h"
 #include "net/socket/client_socket_handle.h"
 #include "net/socket/ssl_error_params.h"
 
 // Welcome to Mac SSL. We've been waiting for you.
 //
 // The Mac SSL implementation is, like the Windows and NSS implementations, a
@@ skipping 1394 matching lines @@
   if (rv < 0 && rv != ERR_IO_PENDING) {
     us->write_io_buf_ = NULL;
     return OSStatusFromNetError(rv);
   }
 
   // always lie to our caller
   return noErr;
 }
 
 }  // namespace net