Except when TBR is active, because it's not clear how to
compute max score for Code-Review label before uploading a change.

Tested with this very own CL:
  To https://chromium.googlesource.com/chromium/tools/depot_tools.git
   * [new branch]        c78de165c7be156bdf8032c0ce3d8bad42778f1c ->
     refs/for/refs/heads/master%ready,notify=ALL,m=Initial_upload,r=ehmaldonado,
         cc=ajp,cc=chromium-reviews@chromium.org,cc=iannucci+depot_tools@chromium.org,
         l=Commit-Queue+1,hashtag=git-cl-upload
R=ehmaldonado

Bug: 877717
Change-Id: I464d9df2814bd830dd608bb881040e2dd3c41dbb
Reviewed-on: https://chromium-review.googlesource.com/c/1307052Reviewed-by: Edward Lesmes <ehmaldonado@chromium.org>
Commit-Queue: Andrii Shyshkalov <tandrii@chromium.org>