Build bustage fix for gcc 2.7 & vc5 - include class interface

before playing with nsCOMPtr. r=travis@aol.net,a=dmose@mozilla.org

layout/html/forms/src/nsGfxTextControlFrame.h

@@ -42,9 +42,9 @@
 #include "nsIDOMKeyEvent.h"
 #include "nsITextContent.h"
 #include "nsHTMLValue.h"
+#include "nsIWebShell.h"
 
 class nsIFrame;
-class nsIWebShell;
 class nsIDOMSelection;