patch 9.1.1348: still E315 with the terminal feature

Problem:  still E315 with the terminal feature
          (user202729)
Solution: call update_topline() in limit_scrollback()
          (Hirohito Higashi)

fixes: #17195
closes: #17196

Signed-off-by: Hirohito Higashi <h.east.727@gmail.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

src/terminal.c

@@ -3455,8 +3455,8 @@ limit_scrollback(term_T *term, garray_T *gap, int update_buffer)
 	    sizeof(sb_line_T) * gap->ga_len);
     if (update_buffer)
     {
-	win_T	    *curwin_save = curwin;
+	win_T *curwin_save = curwin;
-	win_T	    *wp = NULL;
+	win_T *wp = NULL;
 
 	term->tl_scrollback_scrolled -= todo;
 
@@ -3466,14 +3466,11 @@ limit_scrollback(term_T *term, garray_T *gap, int update_buffer)
 	    {
 		curwin = wp;
 		check_cursor();
+		update_topline();
 	    }
 	}
 	curwin = curwin_save;
     }
-
-    // make sure cursor is on a valid line
-    if (curbuf == term->tl_buffer)
-	check_cursor();
 }
 
 /*

src/testdir/test_terminal2.vim

@@ -245,6 +245,10 @@ func Test_termwinscroll()
 endfunc
 
 func Test_termwinscroll_topline()
+  if has('win32')
+    CheckGithubActions
+  endif
+
   set termwinscroll=1000 mouse=a
   terminal
   call assert_equal(2, winnr('$'))

src/version.c

@@ -704,6 +704,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1348,
 /**/
     1347,
 /**/