[wxGTK] Remove wxTLW::RequestUserAttention related backwards compatibility hacks

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@35637 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/gtk/toplevel.h

@@ -62,9 +62,7 @@ public:
 
     virtual bool SetShape(const wxRegion& region);
 
-#if wxABI_VERSION >= 20602
     virtual void RequestUserAttention(int flags = wxUSER_ATTENTION_INFO);
-#endif
 
     virtual bool Show(bool show = TRUE);
 
@@ -110,6 +108,10 @@ public:
     long          m_gdkFunc,
                   m_gdkDecor;
 
+    // private gtk_timeout_add result for mimicing wxUSER_ATTENTION_INFO and
+    // wxUSER_ATTENTION_ERROR difference, -2 for no hint, -1 for ERROR hint, rest for GtkTimeout handle.
+    int m_urgency_hint;
+
 protected:
     // common part of all ctors
     void Init();