Stop using CertStore which is not compatible with PlzNavigate.

ios/web/public/test/test_web_state.mm

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ios/web/public/test/test_web_state.h"
 
 #include <stdint.h>
 
 #include "base/callback.h"
 
@@ skipping 80 matching lines @@
 }
 
 bool TestWebState::IsShowingWebInterstitial() const {
   return false;
 }
 
 WebInterstitial* TestWebState::GetWebInterstitial() const {
   return nullptr;
 }
 
-int TestWebState::GetCertGroupId() const {
-  return 0;
-}
-
 void TestWebState::SetContentIsHTML(bool content_is_html) {
   content_is_html_ = content_is_html;
 }
 
 const base::string16& TestWebState::GetTitle() const {
   return title_;
 }
 
 bool TestWebState::IsLoading() const {
   return is_loading_;
@@ skipping 34 matching lines @@
 shell::InterfaceRegistry* TestWebState::GetMojoInterfaceRegistry() {
   return nullptr;
 }
 
 base::WeakPtr<WebState> TestWebState::AsWeakPtr() {
   NOTREACHED();
   return base::WeakPtr<WebState>();
 }
 
 }  // namespace web