Make CertVerifier a pure virtual interface.

net/socket/ssl_server_socket_unittest.cc

Index: net/socket/ssl_server_socket_unittest.cc
diff --git a/net/socket/ssl_server_socket_unittest.cc b/net/socket/ssl_server_socket_unittest.cc
index 86f444cd99a09cee22cfac78c05b0d6a435e65ef..84d80799c5fd4cd963b01b67538d6b9d0677c70b 100644
--- a/net/socket/ssl_server_socket_unittest.cc
+++ b/net/socket/ssl_server_socket_unittest.cc
@@ -28,11 +28,11 @@
 #include "crypto/rsa_private_key.h"
 #include "net/base/address_list.h"
 #include "net/base/cert_status_flags.h"
-#include "net/base/cert_verifier.h"
 #include "net/base/completion_callback.h"
 #include "net/base/host_port_pair.h"
 #include "net/base/io_buffer.h"
 #include "net/base/ip_endpoint.h"
+#include "net/base/multi_threaded_cert_verifier.h"
 #include "net/base/net_errors.h"
 #include "net/base/net_log.h"
 #include "net/base/ssl_config_service.h"
@@ -307,7 +307,7 @@ class SSLServerSocketTest : public PlatformTest {
   scoped_ptr<net::SSLClientSocket> client_socket_;
   scoped_ptr<net::SSLServerSocket> server_socket_;
   net::ClientSocketFactory* socket_factory_;
-  net::CertVerifier cert_verifier_;
+  net::MultiThreadedCertVerifier cert_verifier_;
 };
 
 // SSLServerSocket is only implemented using NSS.