Add app_shell_browsertests to trybot configurations for chromeos.

Follows https://chromiumcodereview.appspot.com/232053003/
BUG=353600

Review URL: https://codereview.chromium.org/237813002

git-svn-id: http://src.chromium.org/chrome/trunk/src/testing@264290 4ff67af0-8c30-449e-8e8b-ad334ec8d88c
Run apps_browsertests on the ChromiumOS waterfall bots.

BUG=349631

Review URL: https://codereview.chromium.org/208863003

git-svn-id: http://src.chromium.org/chrome/trunk/src/testing@264376 4ff67af0-8c30-449e-8e8b-ad334ec8d88c
Revert 264376 "Run apps_browsertests on the ChromiumOS waterfall..."

> Run apps_browsertests on the ChromiumOS waterfall bots.
> 
> BUG=349631
> 
> Review URL: https://codereview.chromium.org/208863003

TBR=yoz@chromium.org

Review URL: https://codereview.chromium.org/239333013

git-svn-id: http://src.chromium.org/chrome/trunk/src/testing@264382 4ff67af0-8c30-449e-8e8b-ad334ec8d88c
Run app_shell_browsertests on the ChromiumOS waterfall bots.

Note the correct name this time.

BUG=349631
TBR=phajdan.jr@chromium.org
NOTRY=true

Review URL: https://codereview.chromium.org/240023007

git-svn-id: http://src.chromium.org/chrome/trunk/src/testing@264405 4ff67af0-8c30-449e-8e8b-ad334ec8d88c