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.

src/common/evtloopcmn.cpp

@@ -88,11 +88,6 @@ void wxEventLoopBase::OnExit()
         wxTheApp->OnEventLoopExit(this);
 }
 
-void wxEventLoopBase::WakeUpIdle()
-{
-    WakeUp();
-}
-
 bool wxEventLoopBase::ProcessIdle()
 {
     return wxTheApp && wxTheApp->ProcessIdle();