Revert of Remove support for legacy WebKit Notifications

Source/modules/notifications/NotificationClient.h

Index: Source/modules/notifications/NotificationClient.h
diff --git a/Source/modules/notifications/NotificationClient.h b/Source/modules/notifications/NotificationClient.h
index e36dab92e00ad40b033346e731522ee7d69d1080..f918245534f06b2fb95ca25b29d9e59078fbbe83 100644
--- a/Source/modules/notifications/NotificationClient.h
+++ b/Source/modules/notifications/NotificationClient.h
@@ -39,7 +39,7 @@
 namespace WebCore {
 
 class ExecutionContext;
-class Notification;
+class NotificationBase;
 
 class NotificationClient {
 
@@ -51,19 +51,22 @@
     };
 
     // Requests that a notification be shown.
-    virtual bool show(Notification*) = 0;
+    virtual bool show(NotificationBase*) = 0;
 
     // Requests that a notification that has already been shown be canceled.
-    virtual void cancel(Notification*) = 0;
+    virtual void cancel(NotificationBase*) = 0;
 
     // Informs the presenter that a Notification object has been destroyed
     // (such as by a page transition). The presenter may continue showing
     // the notification, but must not attempt to call the event handlers.
-    virtual void notificationObjectDestroyed(Notification*) = 0;
+    virtual void notificationObjectDestroyed(NotificationBase*) = 0;
 
+#if ENABLE(LEGACY_NOTIFICATIONS)
     // Requests user permission to show desktop notifications from a particular
     // script context. The callback parameter should be run when the user has
     // made a decision.
+    virtual void requestPermission(ExecutionContext*, PassOwnPtr<VoidCallback>) = 0;
+#endif
     virtual void requestPermission(ExecutionContext*, PassOwnPtr<NotificationPermissionCallback>) = 0;
 
     // Checks the current level of permission.