get system colors directly from GTK styles, eliminating need for cached wxColor objects

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@55315 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/gtk/toplevel.h

@@ -16,7 +16,6 @@
 
 class WXDLLIMPEXP_CORE wxTopLevelWindowGTK : public wxTopLevelWindowBase
 {
-    DECLARE_EVENT_TABLE()
 public:
     // construction
     wxTopLevelWindowGTK() { Init(); }
@@ -86,9 +85,6 @@ public:
     // GTK callbacks
     virtual void OnInternalIdle();
 
-    // Respond to system colour change
-    void OnSysColourChanged(wxSysColourChangedEvent& event);
-
     // do *not* call this to iconize the frame, this is a private function!
     void SetIconizeState(bool iconic);