Click on Start - Settings - System - Notifications & Actions. Scroll down to find Google Chrome and turn off notifications.
So that is a "feature" of Win10?
That is actually a notification/advertisement coming through Google Chrome.
So you're saying a (potentially) malicious ad (or similar).
And by default (Win10) allows for it to be displayed (like many other nonsense) popups that one may see?
Then you should also scan with ADW Cleaner.
So there is potentially some actual exploit.
As in simply quelling the message does not mean that all is (necessarily) OK.
Note the (what appears to be a) site name in the message.