preparation for allowing to use wxTimer in wxBase (heavily modified patch 1113088):

1. Changed wxTimer to use wxTimerImpl
2. Added Unix-specific generic timer implementation
3. Added wxAppTraits::CreateTimerImpl()


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@45544 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/gtk/utilsgtk.cpp

@@ -24,6 +24,8 @@
 
 #include "wx/unix/execute.h"
 
+#include "wx/gtk/private/timer.h"
+
 #ifdef __WXDEBUG__
     #include "wx/gtk/assertdlg_gtk.h"
     #if wxUSE_STACKWALKER
@@ -286,6 +288,11 @@ wxPortId wxGUIAppTraits::GetToolkitVersion(int *verMaj, int *verMin) const
     return wxPORT_GTK;
 }
 
+wxTimerImpl *wxGUIAppTraits::CreateTimerImpl(wxTimer *timer)
+{
+    return new wxGTKTimerImpl(timer);
+}
+
 #if wxUSE_DETECT_SM
 static wxString GetSM()
 {