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: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@58339 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser