[autofill] Add support for PSL domain matching for password autofill.

content/public/common/password_form.cc

 // Copyright (c) 2011 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 "content/public/common/password_form.h"
 
 namespace content {
 
 PasswordForm::PasswordForm()
     : scheme(SCHEME_HTML),
       password_autocomplete_set(true),
       ssl_valid(false),
       preferred(false),
       blacklisted_by_user(false),
       type(TYPE_MANUAL),
       times_used(0) {
 }
 
 PasswordForm::~PasswordForm() {
 }
 
+bool PasswordForm::IsPublicSuffixMatch() const {
+  return !original_signon_realm.empty();
+}
+
 }  // namespace content