[Offline Pages] Add a GCMAppHandler for offline page prefetch.

chrome/browser/android/offline_pages/prefetch/prefetch_service_factory.h

 // Copyright 2017 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.
 
-#ifndef COMPONENTS_OFFLINE_PAGES_CONTENT_PREFETCH_SERVICE_FACTORY_H_
-#define COMPONENTS_OFFLINE_PAGES_CONTENT_PREFETCH_SERVICE_FACTORY_H_
+#ifndef CHROME_BROWSER_ANDROID_OFFLINE_PAGES_PREFETCH_PREFETCH_SERVICE_FACTORY_H_
+#define CHROME_BROWSER_ANDROID_OFFLINE_PAGES_PREFETCH_PREFETCH_SERVICE_FACTORY_H_
 
 #include "base/macros.h"
 #include "components/keyed_service/content/browser_context_keyed_service_factory.h"
 
 namespace base {
 template <typename T>
 struct DefaultSingletonTraits;
 }  // namespace base
 
 namespace offline_pages {
 
 class PrefetchService;
 
 // A factory to create one PrefetchServiceImpl per browser context. Prefetching
 // Offline Pages is not supported in incognito, so this class uses default
 // implementation of |GetBrowserContextToUse|.
 class PrefetchServiceFactory : public BrowserContextKeyedServiceFactory {
  public:
   static PrefetchServiceFactory* GetInstance();
   static PrefetchService* GetForBrowserContext(
       content::BrowserContext* context);
 
+  // BrowserContextKeyedServiceFactory overrides.
+  bool ServiceIsCreatedWithBrowserContext() const override;
+
  private:
   friend struct base::DefaultSingletonTraits<PrefetchServiceFactory>;
 
   PrefetchServiceFactory();
   ~PrefetchServiceFactory() override {}
 
   KeyedService* BuildServiceInstanceFor(
       content::BrowserContext* context) const override;
 
   DISALLOW_COPY_AND_ASSIGN(PrefetchServiceFactory);
 };
 
 }  // namespace offline_pages
 
-#endif  // COMPONENTS_OFFLINE_PAGES_CONTENT_PREFETCH_SERVICE_FACTORY_H_
+#endif  // CHROME_BROWSER_ANDROID_OFFLINE_PAGES_PREFETCH_PREFETCH_SERVICE_FACTORY_H_