Bug 283345: Description of Profile Manager's <dialogheader> isn't updated when switching from Select Profile- to Manage Profile-mode

r+sr=neil

profile/resources/content/profileManager.js

@@ -277,7 +277,7 @@ function SwitchProfileManagerMode()
 function ChangeCaption( aCaption )
 {
   var caption = document.getElementById( "header" );
-  caption.setAttribute( "value", aCaption );
+  caption.setAttribute( "description", aCaption );
   document.title = aCaption;
 }