Make boottime delay not block file thread BUG=None TEST=Boot on ARM...boottimes shouldn't display but chrome should      still work. We will be stating a file every half second though      until /tmp/uptime-login-prompt-ready is emited.
Make boottime delay not block file thread
BUG=None
TEST=Boot on ARM...boottimes shouldn't display but chrome should
     still work. We will be stating a file every half second though
     until /tmp/uptime-login-prompt-ready is emited.

Review URL: http://codereview.chromium.org/2007010

git-svn-id: http://src.chromium.org/svn/trunk/src@47097 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

Former-commit-id: 101ecf73240c9e8f2000c6fdb3692f8340c35941
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