removed OnIdle() which didn't compile any longer

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@21943 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/cocoa/app.h

@@ -53,9 +53,6 @@ public:
     virtual bool Yield(bool onlyIfNeeded = FALSE);
     virtual void WakeUpIdle() { CocoaRequestIdle(); }
     
-    /* Idle Processing */
-    void OnIdle(wxIdleEvent& event);
-
     virtual bool Initialize(int& argc, wxChar **argv);
     virtual void CleanUp();
     virtual bool CallOnInit();