Document unexpected wxWindowDisabler taskbar UI in wxMSW.

It may be unexpected that the application can still be closed from the taskbar
even if its main window is disabled. Mention this in the documentation and
indicate how to prevent this from happening if required.

Closes #13081.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@67354 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

interface/wx/utils.h

@@ -37,6 +37,14 @@ public:
     /**
         Disables all top level windows of the applications with the exception
         of @a winToSkip if it is not @NULL.
+
+        Notice that under MSW if @a winToSkip appears in the taskbar, the user
+        will be able to close the entire application (even though its main
+        window is disabled) by right clicking on the taskbar icon and selecting
+        the appropriate "Close" command from the context menu. To prevent this
+        from happening you may want to use wxFRAME_TOOL_WINDOW, if applicable,
+        or wxFRAME_NO_TASKBAR style when creating the window that will remain
+        enabled.
     */
     wxWindowDisabler(wxWindow* winToSkip);