Update policy for using TBR.

(1) Add text allowing TBR with relands which previously appeared on the
    sites page.
(2) Add guidance that TBR'ed reverts should be clean and recent.
(3) Make "OWNERS file details" a subsection of "OWNERS files".

Discussed on chromium-dev at: goo.gl/kCw2HK

Change-Id: Ic0329574652926483f9cb33100635f89fa8b0107
Reviewed-on: https://chromium-review.googlesource.com/1217167
Reviewed-by: Dirk Pranke <[email protected]>
Reviewed-by: Wez <[email protected]>
Reviewed-by: Will Harris <[email protected]>
Commit-Queue: Steve Kobes <[email protected]>
Cr-Commit-Position: refs/heads/master@{#590286}
1 file changed