Emit error events if the loading of an object element failed

third_party/WebKit/public/web/WebPlugin.h

 /*
  * Copyright (C) 2009, 2012 Google Inc. All rights reserved.
  * Copyright (C) 2014 Opera Software ASA. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 209 matching lines @@
   // Tells the plugin that the user has stopped the find operation.
   virtual void stopFind() {}
 
   // View rotation types.
   enum RotationType { RotationType90Clockwise, RotationType90Counterclockwise };
   // Whether the plugin can rotate the view of its content.
   virtual bool canRotateView() { return false; }
   // Rotates the plugin's view of its content.
   virtual void rotateView(RotationType type) {}
 
-  virtual bool isPlaceholder() { return true; }
+  virtual bool isPlaceholder() { return placeholder; }
+  virtual void markAsPlaceholder() { placeholder = true; }
 
  protected:
   ~WebPlugin() {}
+  bool placeholder = false;
 };
 
 }  // namespace blink
 
 #endif