Make //content responsible for generating notification Ids

content/public/browser/platform_notification_service.h

Index: content/public/browser/platform_notification_service.h
diff --git a/content/public/browser/platform_notification_service.h b/content/public/browser/platform_notification_service.h
index 0d03ecc86bdd446a8e28e270216c4ded8e91efa3..93adec687a5bd2d34411c4e5478e7917a4e0ab0e 100644
--- a/content/public/browser/platform_notification_service.h
+++ b/content/public/browser/platform_notification_service.h
@@ -55,6 +55,7 @@ class CONTENT_EXPORT PlatformNotificationService {
   // |cancel_callback| argument. This method must be called on the UI thread.
   virtual void DisplayNotification(
       BrowserContext* browser_context,
+      const std::string& notification_id,
       const GURL& origin,
       const PlatformNotificationData& notification_data,
       const NotificationResources& notification_resources,
@@ -65,7 +66,7 @@ class CONTENT_EXPORT PlatformNotificationService {
   // the user. This method must be called on the UI thread.
   virtual void DisplayPersistentNotification(
       BrowserContext* browser_context,
-      int64_t persistent_notification_id,
+      const std::string& notification_id,
       const GURL& service_worker_origin,
       const GURL& origin,
       const PlatformNotificationData& notification_data,
@@ -75,7 +76,7 @@ class CONTENT_EXPORT PlatformNotificationService {
   // |persistent_notification_id|. This method must be called on the UI thread.
   virtual void ClosePersistentNotification(
       BrowserContext* browser_context,
-      int64_t persistent_notification_id) = 0;
+      const std::string& notification_id) = 0;
 
   // Writes the ids of all currently displaying persistent notifications for the
   // given |browser_context| to |displayed_notifications|. Returns whether the