Added wxFrameBase::OnMenuOpen, and wxUSE_IDLEMENUUPDATES in platform.h

Experimental wxUpdateUIEvent::SetUpdateInterval() function to limit
UI update frequency


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@21746 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/os2/window.cpp

@@ -1364,7 +1364,8 @@ void wxWindowOS2::OnIdle(
             (void)GetEventHandler()->ProcessEvent(rEvent);
         }
     }
-    UpdateWindowUI();
+    if (wxUpdateUIEvent::CanUpdate())
+        UpdateWindowUI();
 } // end of wxWindowOS2::OnIdle
 
 //