remove "redo" item that we got from mozilla.

toolkit/content/widgets/textbox.xml

@@ -173,7 +173,6 @@
                                      this.parentNode.doPopupItemEnabling(this);"
                      oncommand="this.parentNode.doCommand(event.originalTarget.getAttribute('cmd'));event.preventBubble();">
         <xul:menuitem label="&undoCmd.label;" accesskey="&undoCmd.accesskey;" cmd="cmd_undo"/>
-        <xul:menuitem label="&redoCmd.label;" accesskey="&redoCmd.accesskey;" cmd="cmd_redo"/>
         <xul:menuseparator/>
         <xul:menuitem label="&cutCmd.label;" accesskey="&cutCmd.accesskey;" cmd="cmd_cut"/>
         <xul:menuitem label="&copyCmd.label;" accesskey="&copyCmd.accesskey;" cmd="cmd_copy"/>