Fix autofill popup controller key press callback registration

ios/chrome/browser/passwords/ios_chrome_password_manager_driver.mm

 // Copyright 2015 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.
 
 #import "ios/chrome/browser/passwords/ios_chrome_password_manager_driver.h"
 
 #include "base/strings/string16.h"
 #include "components/autofill/core/common/password_form.h"
 #include "components/autofill/core/common/password_form_fill_data.h"
 #include "components/password_manager/core/browser/password_generation_manager.h"
@@ skipping 64 matching lines @@
 PasswordAutofillManager*
 IOSChromePasswordManagerDriver::GetPasswordAutofillManager() {
   // TODO(crbug.com/341877): Use PasswordAutofillManager to implement password
   // autofill on iOS.
   return nullptr;
 }
 
 void IOSChromePasswordManagerDriver::ForceSavePassword() {
   NOTIMPLEMENTED();
 }
+
+autofill::AutofillDriver* IOSChromePasswordManagerDriver::GetAutofillDriver() {
+  NOTIMPLEMENTED();
+  return nullptr;
+}