Stop using CertStore which is not compatible with PlzNavigate.

ios/chrome/browser/ssl/ios_chrome_security_state_model_client.mm

Index: ios/chrome/browser/ssl/ios_chrome_security_state_model_client.mm
diff --git a/ios/chrome/browser/ssl/ios_chrome_security_state_model_client.mm b/ios/chrome/browser/ssl/ios_chrome_security_state_model_client.mm
index 8098575e4e4de36f247bedcaacbff163ba5746f0..9cc4f3864e625b5ced17cda842c0ac9d1bb782ff 100644
--- a/ios/chrome/browser/ssl/ios_chrome_security_state_model_client.mm
+++ b/ios/chrome/browser/ssl/ios_chrome_security_state_model_client.mm
@@ -7,7 +7,6 @@
 #include "base/command_line.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram_macros.h"
-#include "ios/web/public/cert_store.h"
 #include "ios/web/public/navigation_item.h"
 #import "ios/web/public/navigation_manager.h"
 #import "ios/web/public/origin_util.h"
@@ -65,11 +64,11 @@ bool IOSChromeSecurityStateModelClient::RetrieveCert(
     scoped_refptr<net::X509Certificate>* cert) {
   web::NavigationItem* item =
       web_state_->GetNavigationManager()->GetVisibleItem();
-  if (!item)
+  if (!item || !item->GetSSL().certificate)
     return false;
 
-  int cert_id = item->GetSSL().cert_id;
-  return web::CertStore::GetInstance()->RetrieveCert(cert_id, cert);
+  *cert = item->GetSSL().certificate;
+  return true;
 }
 
 bool IOSChromeSecurityStateModelClient::UsedPolicyInstalledCertificate() {
@@ -94,7 +93,7 @@ void IOSChromeSecurityStateModelClient::GetVisibleSecurityState(
   const web::SSLStatus& ssl = item->GetSSL();
   state->initial_security_level =
       GetSecurityLevelForSecurityStyle(ssl.security_style);
-  state->cert_id = ssl.cert_id;
+  state->certificate = ssl.certificate;
   state->cert_status = ssl.cert_status;
   state->connection_status = ssl.connection_status;
   state->security_bits = ssl.security_bits;