(hopefully) fixed race condition in installing idle handler (calling wxPostEvent from non-main thread)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@30266 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/gtk1/app.h

@@ -56,6 +56,8 @@ public:
 #endif // __WXDEBUG__
 
     gint            m_idleTag;
+    void RemoveIdleTag();
+    
     unsigned char  *m_colorCube;
 
     // Used by the the wxGLApp and wxGLCanvas class for GL-based X visual