I think users are only sharing their browsing history with Google, and their ISP when browsing the web with a Chromebook laptop or Google Android device. But, if you use Google Chrome on Windows and Apple, you maybe sharing your browsing history with Microsoft, or Apple if MS and Apple track user's browsing history, and send the data back to MS or Apple's server. Google, and your ISP also can track the Windows and Apple version of Chrome. I think the version of Google Chrome for iOS uses the Apple Webkit website rendering engine, so Apple most likely know what you use the iOS version of Chrome for. A lot of third-party antivirus, anti-malware and firewall software for Windows, and Apple OS may also track user's Chrome browsing traffic. But, the Antivirus built-into Chrome OS and newer versions of Android is created by Google, so the Chrome OS and Android Antivirus is only sharing with Google unless you use a third-party Antivirus App for Android.