Chrome Version: <From about:version: Google Chrome 51.0.2699.0>
Chrome OS Version: <From about:version: Platform 8155.0.0>
Chrome OS Platform: <Lars>
Network info: <Captive Portal- WiFi)>

Please specify Cr-* of the system to which this bug/feature applies (add
the label below).

Steps To Reproduce:
(1)Connect to captive portal network.
(2)Logout and login 
(3)Try connecting back

Expected Result:
Should connect without requiring any credentials.

Actual Result:
Credentials required every-time.

How frequently does this problem reproduce? (Always, sometimes, hard to
reproduce?)
Always

What is the impact to the user, and is there a workaround? If so, what is
it?
User need to enter credentials every-time after login/logout or switching networks.

Please provide any additional information below. Attach a screen shot or
log if possible.
logs attached. Will try to reproduce on other builds, devices n update.