Added server-side infrastructure for the thread input structure.
Reimplemented AttachThreadInput() and added GetGUIThreadInfo().

diff --git a/server/request.h b/server/request.h
index 0c744b4..3f1a036 100644
--- a/server/request.h
+++ b/server/request.h
@@ -259,6 +259,8 @@
 DECL_HANDLER(remove_window_property);
 DECL_HANDLER(get_window_property);
 DECL_HANDLER(get_window_properties);
+DECL_HANDLER(attach_thread_input);
+DECL_HANDLER(get_thread_input);
 
 #ifdef WANT_REQUEST_HANDLERS
 
@@ -421,6 +423,8 @@
     (req_handler)req_remove_window_property,
     (req_handler)req_get_window_property,
     (req_handler)req_get_window_properties,
+    (req_handler)req_attach_thread_input,
+    (req_handler)req_get_thread_input,
 };
 #endif  /* WANT_REQUEST_HANDLERS */