Don't make wxEventLoop::WakeUpIdle() virtual

It just forwards to (virtual) WakeUp() and there should be no need to
ever override this method itself (nor even to keep it, except for
backwards compatibility).

No real changes.

include/wx/evtloop.h

@@ -128,8 +128,9 @@ public:
     // idle handling
     // -------------
 
-        // make sure that idle events are sent again
-    virtual void WakeUpIdle();
+        // make sure that idle events are sent again: this is just an obsolete
+        // synonym for WakeUp()
+    void WakeUpIdle() { WakeUp(); }
 
         // this virtual function is called  when the application
         // becomes idle and by default it forwards to wxApp::ProcessIdle() and