Make //content responsible for generating notification Ids

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
index 47d6b755a5031cd4fcda09522f0a57b69cc1d9be..71da1d11c7a8943ae16762e0fc7732c44ddf762d 100644
--- a/content/public/browser/platform_notification_context.h
+++ b/content/public/browser/platform_notification_context.h
@@ -34,14 +34,14 @@ class PlatformNotificationContext
 
   using WriteResultCallback =
       base::Callback<void(bool /* success */,
-                          int64_t /* notification_id */)>;
+                          const std::string& /* 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,
+  virtual void ReadNotificationData(const std::string& notification_id,
                                     const GURL& origin,
                                     const ReadResultCallback& callback) = 0;
 
@@ -55,7 +55,8 @@ class PlatformNotificationContext
 
   // 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.
+  // the notification id when written successfully. The notification ID field
+  // for |database_data| will be generated, and thus must be empty.
   virtual void WriteNotificationData(
       const GURL& origin,
       const NotificationDatabaseData& database_data,
@@ -64,7 +65,7 @@ class PlatformNotificationContext
   // 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,
+  virtual void DeleteNotificationData(const std::string& notification_id,
                                       const GURL& origin,
                                       const DeleteResultCallback& callback) = 0;