Fix regression in upgrade detection in about dialog.
Fix regression in upgrade detection in about dialog.

BUG=67478
TEST=Install SxS, start chrome, open about dialog, notice that it doesn't say to restart if there's no update.

Review URL: http://codereview.chromium.org/6076008

git-svn-id: http://src.chromium.org/svn/trunk/src@70612 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 6a360c916e82437050ed38a48723beb044f84c1c
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