Full Google Chrome removal

The .save file was created by APT from the original .list file that Chrome added. It's intended as a backup and doesn't actually affect anything. The .distUpgrade file was probably created by APT when you when you did a release upgrade (I'm assuming you did). The Chrome package is unaware of them (Chrome didn't have anything to do with their creation), so purging that package leaves these files alone.

Can I just delete them?

Yep.

[A]re there any other changes installing Google Chrome would have made that I need to undo or delete[?]

Without the original package, we can't say for sure.

I am wondering if there is also a log that would tell me all the changes that particular installation made[.]

Nope. Unless you use a HIDS or similar system which keeps track of files in your system, the apt log only states what happened from an overall state (X was removed, Y was installed, etc.).