Fix crash on update screen. Introduced in CL http://codereview.chromium.org/2842024
Fix crash on update screen.
Introduced in CL http://codereview.chromium.org/2842024

BUG= http://crosbug.com/4208
TEST=Execute OOBE, update screen should check for update and proceed.

Review URL: http://codereview.chromium.org/2871022

git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@50768 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