A while back I put together a Linode server for a small project. Because I was lazy I made a private page of web links for the site logs and made the URL something long and obscure with plenty of backslashes that couldn't be spidered or guessed. The main site had no Google analytics and barely any traffic.

When I checked the logs a couple of days later my private log page had been accessed externally. The visitor's IP address was in one of the ranges that belongs to Google.

So... I changed the URL, looked at the new URL in Chrome, and checked again a day later.

Same thing. Someone - or something - from Google was accessing my private URL, based on my Chrome history.

I changed the URL again and switched to Safari.

Nothing.

Clearly, Chrome phones home and Google feels entitled to check new URLs that it can't spider. Safari doesn't phone home. (Or if it does, no one at Apple cares enough to check weird URLs).

I don't think any other conclusion is possible.