Refactor ResourceRequestAllowedNotifier EULA checking into a separate class.

chrome/browser/metrics/variations/eula_accepted_notifier_chromeos.cc

+// Copyright (c) 2013 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 "chrome/browser/metrics/variations/eula_accepted_notifier_chromeos.h"
+
+#include "chrome/browser/chromeos/login/wizard_controller.h"
+#include "chrome/common/chrome_notification_types.h"
+#include "content/public/browser/notification_service.h"
+
+EulaAcceptedNotifierChromeos::EulaAcceptedNotifierChromeos() {
+}
+
+EulaAcceptedNotifierChromeos::~EulaAcceptedNotifierChromeos() {
+}
+
+bool EulaAcceptedNotifierChromeos::IsEulaAccepted() {
+  if (chromeos::WizardController::IsEulaAccepted())
+    return true;
+
+  // Register for the notification, if this is the first time.
+  if (registrar_.IsEmpty()) {
+    // Note that this must listen on AllSources due to the difficulty in knowing
+    // when the WizardController instance is created, and to avoid over-coupling
+    // the Chrome OS code with the VariationsService by directly attaching as an
+    // observer. This is OK because WizardController is essentially a singleton.
+    registrar_.Add(this, chrome::NOTIFICATION_WIZARD_EULA_ACCEPTED,
+                   content::NotificationService::AllSources());
+  }
+  return false;
+}
+
+void EulaAcceptedNotifierChromeos::Observe(
+    int type,
+    const content::NotificationSource& source,
+    const content::NotificationDetails& details) {
+  DCHECK_EQ(chrome::NOTIFICATION_WIZARD_EULA_ACCEPTED, type);
+  // This should only ever be received once. Remove it after this call.
+  DCHECK(!registrar_.IsEmpty());
+  registrar_.Remove(this, chrome::NOTIFICATION_WIZARD_EULA_ACCEPTED,
+                    content::NotificationService::AllSources());
+
+  NotifyObserver();
+}
+
+// static
+EulaAcceptedNotifier* EulaAcceptedNotifier::Create() {
+#if defined(GOOGLE_CHROME_BUILD)
+  return new EulaAcceptedNotifierChromeos;
+#else
+  return NULL;
+#endif
+}