patch 9.1.0172: More code can use ml_get_buf_len() instead of STRLEN()

Problem:  More code can use ml_get_buf_len() instead of STRLEN().
Solution: Change more STRLEN() calls to ml_get_buf_len().  Also do not
          set ml_line_textlen in ml_replace_len() if "has_props" is set,
          because "len_arg" also includes the size of text properties in
          that case. (zeertzjq)

closes: #14183

Signed-off-by: zeertzjq <zeertzjq@outlook.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/insexpand.c b/src/insexpand.c
index 0847b6c..5d82e30 100644
--- a/src/insexpand.c
+++ b/src/insexpand.c
@@ -3297,8 +3297,7 @@
 	    // buffer, so that word at start of buffer is found
 	    // correctly.
 	    st->first_match_pos.lnum = st->ins_buf->b_ml.ml_line_count;
-	    st->first_match_pos.col =
-		(colnr_T)STRLEN(ml_get(st->first_match_pos.lnum));
+	    st->first_match_pos.col = ml_get_len(st->first_match_pos.lnum);
 	}
 	st->last_match_pos = st->first_match_pos;
 	compl_type = 0;