patch 8.0.0611: the screen is not redrawn after sending t_u7

Problem:    When t_u7 is sent a few characters in the second screen line are
            overwritten and not redrawn later. (Rastislav Barlik)
Solution:   Move redrawing the screen to after overwriting the characters.

Author: brammool

src/main.c

@@ -783,6 +783,11 @@ vim_main2(void)
     if (params.n_commands > 0)
 	exe_commands(&params);
 
+#if defined(FEAT_TERMRESPONSE) && defined(FEAT_MBYTE)
+    /* Must be done before redrawing, puts a few characters on the screen. */
+    may_req_ambiguous_char_width();
+#endif
+
     RedrawingDisabled = 0;
     redraw_all_later(NOT_VALID);
     no_wait_return = FALSE;
@@ -796,9 +801,6 @@ vim_main2(void)
      * argument doesn't make it appear in the shell Vim was started from. */
     may_req_termresponse();
 
-# if defined(FEAT_MBYTE)
-    may_req_ambiguous_char_width();
-# endif
     may_req_bg_color();
 #endif
 

src/term.c

@@ -3333,9 +3333,13 @@ may_req_ambiguous_char_width(void)
 	 out_str(T_U7);
 	 u7_status = U7_SENT;
 	 out_flush();
+
+	 /* This overwrites a few characters on the screen, a redraw is needed
+	  * after this. Clear them out for now. */
 	 term_windgoto(1, 0);
 	 out_str((char_u *)"  ");
 	 term_windgoto(0, 0);
+
 	 /* check for the characters now, otherwise they might be eaten by
 	  * get_keystroke() */
 	 out_flush();

src/version.c

@@ -764,6 +764,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    611,
 /**/
     610,
 /**/