Handle WM_*MENU* events in wxWindow.

Contrary to MSDN implications, at least some of these messages are not
actually sent to the TLW for popup menus, but to the owning window or
even its parent window (!).

Move the handling of these events from wxTLW to wxWindow.  Move menu
depth tracking to wxFrame, because it only makes sense for frame's
menus and move DoGiveHelp() from wxTLW to wxFrame.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@76721 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/msw/window.h

@@ -535,6 +535,19 @@ public:
     // behaviour
     virtual void OnInternalIdle();
 
+#if wxUSE_MENUS && !defined(__WXUNIVERSAL__)
+    virtual bool HandleMenuSelect(WXWORD nItem, WXWORD nFlags, WXHMENU hMenu);
+
+    // handle WM_(UN)INITMENUPOPUP message to generate wxEVT_MENU_OPEN/CLOSE
+    bool HandleMenuPopup(wxEventType evtType, WXHMENU hMenu);
+
+    // Command part of HandleMenuPopup() and HandleExitMenuLoop().
+    virtual bool DoSendMenuOpenCloseEvent(wxEventType evtType, wxMenu* menu, bool popup);
+
+    // Find the menu corresponding to the given handle.
+    virtual wxMenu* MSWFindMenuFromHMENU(WXHMENU hMenu);
+#endif // wxUSE_MENUS && !__WXUNIVERSAL__
+
 protected:
     // this allows you to implement standard control borders without
     // repeating the code in different classes that are not derived from