net: remove DNS certificate checking code.

net/http/http_network_session.h

Index: net/http/http_network_session.h
diff --git a/net/http/http_network_session.h b/net/http/http_network_session.h
index 5dcf825fc657a74c5de78b91503bd2abda87b1b6..2ccec506b8b7ef4311740a1f4ff85df825af7d68 100644
--- a/net/http/http_network_session.h
+++ b/net/http/http_network_session.h
@@ -27,7 +27,6 @@ namespace net {
 
 class CertVerifier;
 class ClientSocketFactory;
-class DnsCertProvenanceChecker;
 class HostResolver;
 class HttpAuthHandlerFactory;
 class HttpNetworkSessionPeer;
@@ -57,7 +56,6 @@ class NET_EXPORT HttpNetworkSession
           cert_verifier(NULL),
           origin_bound_cert_service(NULL),
           transport_security_state(NULL),
-          dns_cert_checker(NULL),
           proxy_service(NULL),
           ssl_host_info_factory(NULL),
           ssl_config_service(NULL),
@@ -71,7 +69,6 @@ class NET_EXPORT HttpNetworkSession
     CertVerifier* cert_verifier;
     OriginBoundCertService* origin_bound_cert_service;
     TransportSecurityState* transport_security_state;
-    DnsCertProvenanceChecker* dns_cert_checker;
     ProxyService* proxy_service;
     SSLHostInfoFactory* ssl_host_info_factory;
     std::string ssl_session_cache_shard;