refactor(options): use schar_T representation for fillchars and listchars

A bit big, but practically it was a lot simpler to change over all
fillchars and all listchars at once, to not need to maintain two
parallel implementations.

This is mostly an internal refactor, but it also removes an arbitrary
limitation: that 'fillchars' and 'listchars' values can only be
single-codepoint characters. Now any character which fits into a single
screen cell can be used.

1 files changed, 3 insertions, 3 deletions

diff --git a/src/nvim/window.c b/src/nvim/window.c
index c123de0f77..6a305f9b2f 100644
--- a/src/nvim/window.c
+++ b/src/nvim/window.c
@@ -5662,7 +5662,7 @@ void win_setheight_win(int height, win_T *win)
     // If there is extra space created between the last window and the command
     // line, clear it.
     if (full_screen && msg_scrolled == 0 && row < cmdline_row) {
-      grid_fill(&default_grid, row, cmdline_row, 0, Columns, ' ', ' ', 0);
+      grid_clear(&default_grid, row, cmdline_row, 0, Columns, 0);
       if (msg_grid.chars) {
         clear_cmdline = true;
       }
@@ -6145,7 +6145,7 @@ void win_drag_status_line(win_T *dragwin, int offset)
     }
   }
   int row = win_comp_pos();
-  grid_fill(&default_grid, row, cmdline_row, 0, Columns, ' ', ' ', 0);
+  grid_clear(&default_grid, row, cmdline_row, 0, Columns, 0);
   if (msg_grid.chars) {
     clear_cmdline = true;
   }
@@ -6640,7 +6640,7 @@ void command_height(void)
 
       // clear the lines added to cmdline
       if (full_screen) {
-        grid_fill(&default_grid, cmdline_row, Rows, 0, Columns, ' ', ' ', 0);
+        grid_clear(&default_grid, cmdline_row, Rows, 0, Columns, 0);
       }
       msg_row = cmdline_row;
       redraw_cmdline = true;