Added wxBORDER_THEME, wxWindow::GetDefaultBorderForControl(), wxWindow::CanApplyThemeBorder().

wxTextCtrl and wxSearchCtrl now get the correct border on wxMSW, and the wxRichTextCtrl sample
also now demonstrates correct borders.



git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@47927 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/bookctrl.h

@@ -233,6 +233,9 @@ public:
     // we don't want focus for ourselves
     virtual bool AcceptsFocus() const { return false; }
 
+    // returns true if the platform should explicitly apply a theme border
+    virtual bool CanApplyThemeBorder() const { return false; }
+
 protected:
     // flags for DoSetSelection()
     enum