Fix chromeos browser_tests crash by skipping EnsurePrivateKey if device is not owned.
Fix chromeos browser_tests crash by skipping EnsurePrivateKey if device is not owned.

BUG=none.
TEST=ChromeOS buildbot should be green.
TBR=cmasone@chromium.org

git-svn-id: http://src.chromium.org/svn/trunk/src@58339 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: f64541517b38d47d4398f0a11ee98a46a50503d8
meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser,meego-tablet-ux/meego-app-browser