Fixing wxMicroWindows compilation

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@12745 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/app.cpp

@@ -463,6 +463,7 @@ bool wxApp::UnregisterWindowClasses()
 {
     bool retval = TRUE;
 
+#ifndef __WXMICROWIN__
     // frame window class.
     if ( !UnregisterClass(wxFrameClassName, wxhInstance) )
     {
@@ -541,7 +542,8 @@ bool wxApp::UnregisterWindowClasses()
 
         retval = FALSE;
     }
-
+#endif
+    // __WXMICROWIN__
     return retval;
 }