patch 8.0.1026: GTK on-the-spot input has problems

Problem:    GTK on-the-spot input has problems. (Gerd Wachsmuth)
Solution:   Support over-the-spot. (Yukihiro Nakadaira, Ketn Takata, closes
            #1215)
diff --git a/src/ex_getln.c b/src/ex_getln.c
index 74d7937..d0f2bfe 100644
--- a/src/ex_getln.c
+++ b/src/ex_getln.c
@@ -3468,7 +3468,8 @@
 
     windgoto(msg_row, msg_col);
 #if defined(FEAT_XIM) && defined(FEAT_GUI_GTK)
-    redrawcmd_preedit();
+    if (p_imst == IM_ON_THE_SPOT)
+	redrawcmd_preedit();
 #endif
 #ifdef MCH_CURSOR_SHAPE
     mch_update_cursor();