Update trooper doc with chrome-infra chat.

BUG=skia:

GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=3745
NOTRY=true
DOCS_PREVIEW= https://skia.org/?cl=3745

Change-Id: Icc9b52a7b4bc90f4ef8d8b952d49663f74104ba9
Reviewed-on: https://skia-review.googlesource.com/3745
Reviewed-by: Ravi Mistry <rmistry@google.com>
Commit-Queue: Ben Wagner <benjaminwagner@google.com>
1 file changed