patch 9.0.0154: text properties wrong after splitting a line

Problem:    Text properties wrong after splitting a line.
Solution:   Check for text properties after the line. (closes #10857)
diff --git a/src/ops.c b/src/ops.c
index 0cd5f72..5ee2638 100644
--- a/src/ops.c
+++ b/src/ops.c
@@ -1944,7 +1944,7 @@
 }
 
 /*
- * Join 'count' lines (minimal 2) at cursor position.
+ * Join 'count' lines (minimal 2) at the cursor position.
  * When "save_undo" is TRUE save lines for undo first.
  * Set "use_formatoptions" to FALSE when e.g. processing backspace and comment
  * leaders should not be removed.