AU: Set connection timeout to 30 seconds.
AU: Set connection timeout to 30 seconds.

A slow connect doesn't count toward the timeouts we had, so they could
drag on for many minutes. This sets it to 30 seconds.

BUG=chromium-os:14072
TEST=tested on device with captive portal

Change-Id: I83ae9880e9434b95582f7f93321db9afba6e7585

Review URL: http://codereview.chromium.org/6883076

mjg59/update_engine,endocode/update_engine,marineam/update_engine,marineam/update_engine,mjg59/update_engine,endocode/update_engine,marineam/update_engine,mjg59/update_engine,marineam/update_engine,endocode/update_engine