removed tasksOverlay.xul because it's already included from navigatorOverlay.xul. r=saari/brade, rs=hyatt. bug# 78322.

xpfe/global/resources/content/hiddenWindow.xul

@@ -21,7 +21,6 @@ Rights Reserved.
 Contributor(s): ______________________________________. -->
 
 <?xul-overlay href="chrome://navigator/content/navigatorOverlay.xul"?>
-<?xul-overlay href="chrome://communicator/content/tasksOverlay.xul"?>
 
 <!-- hiddenwindow is a "minimal" XUL window intended for creating the,
      er, hidden window.  This window is never shown, but on platforms