patch 8.1.2228: screenpos() returns wrong values when 'number' is set

Problem:    screenpos() returns wrong values when 'number' is set. (Ben
            Jackson)
Solution:   Compare the column with the window width. (closes #5133)

src/move.c

@@ -1217,7 +1217,7 @@ textpos2screenpos(
 	    col -= rowoff * width;
 	}
 	col -= wp->w_leftcol;
-	if (col >= width)
+	if (col >= wp->w_width)
 	    col = -1;
 	if (col >= 0)
 	    coloff = col - scol + wp->w_wincol + 1;

src/testdir/test_cursor_func.vim

@@ -100,3 +100,18 @@ func Test_screenpos()
   close
   bwipe!
 endfunc
+
+func Test_screenpos_number()
+  rightbelow new
+  rightbelow 73vsplit
+  call setline (1, repeat('x', 66))
+  setlocal number
+  redraw
+  let winid = win_getid()
+  let [winrow, wincol] = win_screenpos(winid)
+  let pos = screenpos(winid, 1, 66)
+  call assert_equal(winrow, pos.row)
+  call assert_equal(wincol + 66 + 3, pos.col)
+  close
+  bwipe!
+endfunc

src/version.c

@@ -741,6 +741,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    2228,
 /**/
     2227,
 /**/