The final improvement of the patch, better comments, was never
included in the CL that got checked in. Here they are.

Bug: 920591
Change-Id: I2a5f7f67d4bbc5b40fdb0e7021795cd204d6f0c8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/1583772
Auto-Submit: Daniel Bratell <bratell@opera.com>
Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Commit-Queue: Daniel Bratell <bratell@opera.com>