To Revision 16b370abe6f4b59efea00377473b5dddb438defb.

Also make roll.py executable (chmod u+x roll.py).

Change-Id: Ib3b3767f7fc9c3eef044779c142f62f3d6923242
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1568651Reviewed-by: Alexei Filippov <alph@chromium.org>
Commit-Queue: Johannes Henkel <johannes@chromium.org>
Cr-Commit-Position: refs/heads/master@{#60883}