Post Git switch: Update codereview.settings and remove drover.properties

The key in codereview.settings only made sense for committing to SVN.
The drover.properties is of no use, since drover doesn't support Git.

BUG=chromium:412012

Review URL: https://webrtc-codereview.appspot.com/46669004

Cr-Commit-Position: refs/heads/master@{#8847}
2 files changed