Derive wxStatusBar from wxControl and not wxWindow.

wxStatusBar is no less a control than wxToolBar and deriving it from wxControl
gives access to convenient native control creation functions under MSW (which
will be used by the next commit).

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@66226 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

interface/wx/statusbr.h

@@ -83,7 +83,7 @@ public:
 
     @see wxStatusBarPane, wxFrame, @ref page_samples_statbar
 */
-class wxStatusBar : public wxWindow
+class wxStatusBar : public wxControl
 {
 public:
     /**