Support DOM events in the API reference template.

This enables events in an API to be flagged as DOM events,
giving them a separate schema, TOC section, and reference
presentation.

NOTRY=true

Review URL: https://codereview.chromium.org/25771002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@226803 0039d316-1c4b-4281-b951-d872f2087c98
Test user removal scenario.

BUG=265589
R=ygorshenin@chromium.org
NOTRY=true

Review URL: https://codereview.chromium.org/25870004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@226804 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 226804