Remove NotificationDelegate::process_id().

chrome/browser/notifications/message_center_notification_manager.h

Index: chrome/browser/notifications/message_center_notification_manager.h
diff --git a/chrome/browser/notifications/message_center_notification_manager.h b/chrome/browser/notifications/message_center_notification_manager.h
index 4347096884e7d0de89f4f4b3a975ee34a9688e85..918fb11c7222df4a3da4ec530b054eb0526e9667 100644
--- a/chrome/browser/notifications/message_center_notification_manager.h
+++ b/chrome/browser/notifications/message_center_notification_manager.h
@@ -177,10 +177,6 @@ class MessageCenterNotificationManager
     Profile* profile() const { return profile_; }
     const Notification& notification() const { return notification_; }
 
-    // Returns extension_id if the notification originates from an extension,
-    // empty string otherwise.
-    std::string GetExtensionId();
-
     // Route a new notification to an app/extension.
     void AddToAlternateProvider(const std::string extension_id);