Insure that messages are posted to the main threads event loop,

instead of sending them to the thread-local event loop
        (which typically does not exist under wxWindows).


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@23421 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/os2/private.h

@@ -268,6 +268,20 @@ WXDLLEXPORT HINSTANCE wxGetInstance();
 
 WXDLLEXPORT void wxSetInstance(HINSTANCE hInst);
 
+#include "wx/thread.h"
+static inline MRESULT MySendMsg(HWND hwnd, ULONG ulMsgid,
+                                MPARAM mpParam1, MPARAM mpParam2)
+{
+    MRESULT vRes;
+    vRes = ::WinSendMsg(hwnd, ulMsgid, mpParam1, mpParam2);
+#if wxUSE_THREADS
+    if (!wxThread::IsMain())
+        ::WinPostMsg(hwnd, ulMsgid, mpParam1, mpParam2);
+#endif
+    return vRes;
+}
+#define WinSendMsg MySendMsg
+
 #if wxUSE_GUI
 
 WXDLLEXPORT void wxDrawBorder( HPS     hPS