net: remove DNS certificate checking code.

chrome/browser/io_thread.cc

Index: chrome/browser/io_thread.cc
diff --git a/chrome/browser/io_thread.cc b/chrome/browser/io_thread.cc
index 8e00a2b3957b03cb5cc879addd5cd5f33398d648..63c76013b9ded5a9bb648de7e291d1d498455aad 100644
--- a/chrome/browser/io_thread.cc
+++ b/chrome/browser/io_thread.cc
@@ -41,7 +41,6 @@
 #include "net/base/cert_verifier.h"
 #include "net/base/cookie_monster.h"
 #include "net/base/default_origin_bound_cert_store.h"
-#include "net/base/dnsrr_resolver.h"
 #include "net/base/host_cache.h"
 #include "net/base/host_resolver.h"
 #include "net/base/host_resolver_impl.h"
@@ -59,7 +58,6 @@
 #include "net/proxy/proxy_config_service.h"
 #include "net/proxy/proxy_script_fetcher_impl.h"
 #include "net/proxy/proxy_service.h"
-#include "net/socket/dns_cert_provenance_checker.h"
 
 #if defined(USE_NSS)
 #include "net/ocsp/nss_ocsp.h"
@@ -447,7 +445,6 @@ void IOThread::Init() {
   globals_->host_resolver.reset(
       CreateGlobalHostResolver(net_log_));
   globals_->cert_verifier.reset(new net::CertVerifier);
-  globals_->dnsrr_resolver.reset(new net::DnsRRResolver);
   globals_->transport_security_state.reset(new net::TransportSecurityState(""));
   globals_->ssl_config_service = GetSSLConfigService();
   globals_->http_auth_handler_factory.reset(CreateDefaultAuthHandlerFactory(
@@ -663,7 +660,6 @@ void IOThread::InitSystemRequestContextOnIOThread() {
       globals_->system_origin_bound_cert_service.get();
   system_params.transport_security_state =
       globals_->transport_security_state.get();
-  system_params.dns_cert_checker = NULL;
   system_params.ssl_host_info_factory = NULL;
   system_params.proxy_service = globals_->system_proxy_service.get();
   system_params.ssl_config_service = globals_->ssl_config_service.get();