mingw compilation fixc

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@12281 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/docview.h

@@ -20,6 +20,7 @@
 #include "wx/list.h"
 #include "wx/cmndata.h"
 #include "wx/string.h"
+#include "wx/frame.h"
 
 #if wxUSE_PRINTING_ARCHITECTURE
     #include "wx/print.h"

include/wx/html/helpfrm.h

@@ -33,6 +33,7 @@
 #include "wx/stattext.h"
 #include "wx/html/htmlwin.h"
 #include "wx/html/htmprint.h"
+class WXDLLEXPORT wxButton;
 
 
 // style flags for the Help Frame