ENVIRONMENT and STATS
For syncing clients:
Chrome Version :50.0.2661.102
 
i have tried to login two different email address in two different tab. however it is not happening in reality.

Initially, i have login my email address in one tab and i tried to login another email id in another tab. But the email id which i login initially is opening in another tab.

REPRO STEPS:

1. Open Chrome browser
2. Type Gmail.com in address bar
3. Login with your email id
4. Open another tab and type gmail.com


ACTUAL RESULTS
After doing above steps, the first email address which i logged in, has signed in another tab.

EXPECTED RESULTS
I expect when one tab has logged in with a email id and opened another tab typed 
gmal.com ->another tab should open the gmail home page with user id and password and it should not signed in automatically.
ADDITIONAL INFO
Anything else which may help us debug the issue; screenshots of error
messages or states are always helpful.