Initial framework setup and skeleton for BackgroundFetchContext

content/browser/background_fetch/background_fetch_context.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 CONTENT_BROWSER_BACKGROUND_FETCH_BACKGROUND_FETCH_CONTEXT_H_
+#define CONTENT_BROWSER_BACKGROUND_FETCH_BACKGROUND_FETCH_CONTEXT_H_
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "content/browser/background_fetch/background_fetch_data_manager.h"
+#include "content/browser/service_worker/service_worker_context_observer.h"
+#include "content/common/content_export.h"
+
+namespace content {
+
+class BrowserContext;
+class FetchRequest;
+class ServiceWorkerContextWrapper;
+
+// The BackgroundFetchContext is the central moderator of ongoing background
+// fetch requests from the Mojo service and from other callers.
+// Background Fetch requests function similar to normal fetches except that
+// they are persistent across Chromium or service worker shutdown.
+class CONTENT_EXPORT BackgroundFetchContext
+    : public ServiceWorkerContextObserver,
+      public base::RefCountedThreadSafe<BackgroundFetchContext> {
+ public:
+  // The BackgroundFetchContext will watch the ServiceWorkerContextWrapper so
+  // that it can respond to service worker events such as unregister.
+  explicit BackgroundFetchContext(

[Peter Beverloo, 2017/02/13 18:35:05]

nit: `explicit` is only necessary for constructors that take a single argument

[harkness, 2017/02/14 13:52:46]

Done.

+      BrowserContext* browser_context,
+      const scoped_refptr<ServiceWorkerContextWrapper>& context);
+
+  // Init and Shutdown are for use on the UI thread when the StoragePartition is
+  // being setup and torn down.
+  void Init();
+
+  // Shutdown must be called before deleting this. Call on the UI thread.
+  void Shutdown();
+
+  // ServiceWorkerContextObserver methods.
+  void OnRegistrationDeleted(int64_t registration_id,
+                             const GURL& pattern) override;
+
+  void CreateRequest(const FetchRequest& fetch_request);
+
+ private:
+  friend class base::RefCountedThreadSafe<BackgroundFetchContext>;
+  ~BackgroundFetchContext() override;
+
+  BrowserContext* browser_context_;
+  scoped_refptr<ServiceWorkerContextWrapper> service_worker_context_;
+  BackgroundFetchDataManager background_fetch_data_manager_;
+
+  DISALLOW_COPY_AND_ASSIGN(BackgroundFetchContext);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_BACKGROUND_FETCH_BACKGROUND_FETCH_CONTEXT_H_