Skip timestamp validation for cached Chrome OS user policy.

Devices that can't keep their clocks correct will otherwise ignore the
policy. We're doing the same for device policy already, and the
timestamp checks remain in place for policy updates, so this is OK.

BUG=chromium:347846

Review URL: https://codereview.chromium.org/184373002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@255126 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 255126
Disable redirects in component builds (for now at least).

BUG=349423
R=mark@chromium.org

Review URL: https://codereview.chromium.org/177113010

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@255127 0039d316-1c4b-4281-b951-d872f2087c98
Reland "Add base::TimeDelta::Max()" again.

Webkit layout tests found more media logs serializing infinite
durations to JSON.

R=scherkus@chromium.org
TBR=ajwong@chromium.org,jar@chromium.org,jamesr@chomium.org,acolwell@chromium.org,nick@chromium.org
BUG=None

Review URL: https://codereview.chromium.org/186683002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@255128 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 255128