Expose bits of the Web Notification database in the //content API.

content/public/browser/platform_notification_context.h

Index: content/public/browser/platform_notification_context.h
diff --git a/content/public/browser/platform_notification_context.h b/content/public/browser/platform_notification_context.h
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+++ b/content/public/browser/platform_notification_context.h
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+// 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.
+
+#ifndef CONTENT_PUBLIC_BROWSER_PLATFORM_NOTIFICATION_CONTEXT_H_
+#define CONTENT_PUBLIC_BROWSER_PLATFORM_NOTIFICATION_CONTEXT_H_
+
+#include <stdint.h>
+
+#include "base/callback.h"
+#include "base/memory/ref_counted.h"
+
+class GURL;
+
+namespace content {
+
+struct NotificationDatabaseData;
+
+// Represents the storage context for persistent Web Notifications, specific to
+// the storage partition owning the instance. All methods defined in this
+// interface may only be used on the IO thread.
+class PlatformNotificationContext
+    : public base::RefCountedThreadSafe<PlatformNotificationContext> {
+ public:
+  using ReadResultCallback =
+      base::Callback<void(bool /* success */,
+                          const NotificationDatabaseData&)>;
+
+  using WriteResultCallback =
+      base::Callback<void(bool /* success */,
+                          int64_t /* notification_id */)>;
+
+  using DeleteResultCallback = base::Callback<void(bool /* success */)>;
+
+  // Reads the data associated with |notification_id| belonging to |origin|
+  // from the database. |callback| will be invoked with the success status
+  // and a reference to the notification database data when completed.
+  virtual void ReadNotificationData(int64_t notification_id,
+                                    const GURL& origin,
+                                    const ReadResultCallback& callback) = 0;
+
+  // Writes the data associated with a notification to a database. When this
+  // action completed, |callback| will be invoked with the success status and
+  // the persistent notification id when written successfully.
+  virtual void WriteNotificationData(
+      const GURL& origin,
+      const NotificationDatabaseData& database_data,
+      const WriteResultCallback& callback) = 0;
+
+  // Deletes all data associated with |notification_id| belonging to |origin|
+  // from the database. |callback| will be invoked with the success status
+  // when the operation has completed.
+  virtual void DeleteNotificationData(int64_t notification_id,
+                                      const GURL& origin,
+                                      const DeleteResultCallback& callback) = 0;
+
+ protected:
+  friend class base::RefCountedThreadSafe<PlatformNotificationContext>;
+
+  virtual ~PlatformNotificationContext() {}
+};
+
+}  // namespace content
+
+#endif  // CONTENT_PUBLIC_BROWSER_PLATFORM_NOTIFICATION_CONTEXT_H_