Make CertVerifier a pure virtual interface.

chrome/browser/net/connection_tester.cc

Index: chrome/browser/net/connection_tester.cc
diff --git a/chrome/browser/net/connection_tester.cc b/chrome/browser/net/connection_tester.cc
index 00e7482d8e9062cda4f1c80383d70c8638ec0e7e..1f738d6d2bfd239aea3d103e8f52ead88ccbfb1a 100644
--- a/chrome/browser/net/connection_tester.cc
+++ b/chrome/browser/net/connection_tester.cc
@@ -14,10 +14,10 @@
 #include "base/utf_string_conversions.h"
 #include "chrome/browser/importer/firefox_proxy_settings.h"
 #include "chrome/common/chrome_switches.h"
-#include "net/base/cert_verifier.h"
 #include "net/base/cookie_monster.h"
 #include "net/base/host_resolver.h"
 #include "net/base/io_buffer.h"
+#include "net/base/multi_threaded_cert_verifier.h"
 #include "net/base/net_errors.h"
 #include "net/base/net_util.h"
 #include "net/base/ssl_config_service_defaults.h"
@@ -69,7 +69,7 @@ class ExperimentURLRequestContext : public net::URLRequestContext {
 
     // The rest of the dependencies are standard, and don't depend on the
     // experiment being run.
-    storage_.set_cert_verifier(new net::CertVerifier);
+    storage_.set_cert_verifier(new net::MultiThreadedCertVerifier);
     storage_.set_ftp_transaction_factory(
         new net::FtpNetworkLayer(host_resolver()));
     storage_.set_ssl_config_service(new net::SSLConfigServiceDefaults);