Ignore invalid file notification events

See #18953

src/msw/fswatcher.cpp

@@ -385,6 +385,8 @@ int wxIOCPThread::Native2WatcherFlags(int flags)
 
         // ignored as it should always be matched with ***_OLD_NAME
         { FILE_ACTION_RENAMED_NEW_NAME, 0 },
+        // ignore invalid event
+        { 0, 0 },
     };
 
     for (unsigned int i=0; i < WXSIZEOF(flag_mapping); ++i) {