Also propagate wxEVT_UPDATE_UI to the child MDI frame.

It seems to make sense to handle wxEVT_UPDATE_UI in the same way as wxEVT_MENU
as they are often used together. This allows to handle e.g. toolbar buttons
entirely in the child MDI frame, without any involvement from the parent.

See #14314.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@74276 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/mdi.cpp

@@ -702,7 +702,8 @@ bool wxMDIParentFrame::TryBefore(wxEvent& event)
 {
     // menu (and toolbar) events should be sent to the active child frame
     // first, if any
-    if ( event.GetEventType() == wxEVT_MENU )
+    if ( event.GetEventType() == wxEVT_MENU ||
+            event.GetEventType() == wxEVT_UPDATE_UI )
     {
         wxMDIChildFrame * const child = GetActiveChild();
         if ( child && child->ProcessWindowEventLocally(event) )