updated for version 7.3.1303
Problem:    Undo is synced whenever CTRL-R = is called, breaking some plugins.
Solution:   Only break undo when calling setline() or append().
diff --git a/src/testdir/test61.ok b/src/testdir/test61.ok
index 0e3a525..ea4b473 100644
--- a/src/testdir/test61.ok
+++ b/src/testdir/test61.ok
@@ -44,3 +44,6 @@
 
 a
 b
+c
+12
+d