No, I believe it is because the Chrome as a browser works in conjunction with Gmail and other google properties' logins to kinda figure out that you're a human.
One of the things, if it ever gets there, would be for the anti-trust probe, if any, to look at how Google shares data between its browser, Chrome, and it's other services.
How would the website code communicate with the browser, unless it was some open API you can refer to. As for "in conjunction with Gmail", yes that's called cookies.
From my understanding, that's just expanded cookies. The Chrome frame can see the cookie from your Gmail, and also log you in the browser, and vice versa. Nothing magical going on, just cookies.
