DTD file for Editor Advanced Edit dialog. Forgot to check this in earlier - Fixes 20606

editor/ui/dialogs/locale/en-US/EdAdvancedEdit.dtd

@@ -37,3 +37,7 @@
 <!ENTITY AddJSEAttributeLabel.label     "Add a JavaScript Event Handler">
 <!ENTITY AddHTMLAttributeLabel.label    "Add a HTML Attribute">
 <!ENTITY AddCSSAttributeLabel.label     "Add a Style Attribute">
+
+<!ENTITY context.RemoveAttribute.label  "Remove Attribute">
+<!ENTITY context.AddAttribute.label     "Add Attribute">
+