de0u Since the official directions exist and work
The official directions reference an old version (35.0.2 vs. current 36.0, where a "use-after-free in libusb backend" was fixed!) and don't install anything. They add the binaries to $PATH for the current shell. After restarting the terminal, you'll end up in the same position you started in.
It also doesn't look like Google provides Sha-Sums on their download page. I agree that a check should be performed, but I guess Google doesn't? I could provide my own, but that might too be compromised already, so I omitted that.
As for overwriting binaries installed by apt - I am not aware what exactly that would break, but sure, you could always uninstall the apt version first to be sure.