Updated Code of Conduct.

After an email thread to community@ it was decided to be specific about who is intended to abide
by the code of conduct.

Change-Id: I3efc1b8a569effd8cbd1b964d9b247fea5ce5a80
Reviewed-on: https://chromium-review.googlesource.com/799710Reviewed-by: Rachel Blum <groby@chromium.org>
Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Reviewed-by: Brett Wilson <brettw@chromium.org>
Commit-Queue: Mike Lawther <mikelawther@chromium.org>
Cr-Commit-Position: refs/heads/master@{#521031}

CODE_OF_CONDUCT.md

@@ -5,7 +5,8 @@ diverse, welcoming community. Below is our community code of conduct, which
 applies to our repos and organizations, issue trackers, mailing lists,
 blog content, and any other Chromium-supported communication group, as
 well as any private communication initiated in the context of these
-spaces.
+spaces. This code of conduct must be followed by everyone contributing to
+the Chromium project, regardless of affiliation or position.
 
 Simply put, community discussions should be