To repro:
- install Chrome in a usual place
- set TMP to some dir on a different volume from %LOCALAPPDATA%/%PROGRAMFILES(X86)%
- uninstall Chrome

some files are left behind.

This is happening because setup.exe tries to MoveFileEx itself into TMP so that the Chrome app tree can be deleted. It then jumps through hoops to delete itself from TMP. We should do better to handle this case. Perhaps the files can be painted with delete-on-close if the move fails? Perhaps the cleanup job (which deletes the file from TMP) can be given the job of deleting the original files (be careful, though, we don't want to delete files put into place because of a reinstall!). Perhaps the files should be moved up a few layers in the directory tree into a dir that we name "Temp" and then deleted from the other proc? Many possiblities.