Comment 7 for bug 1265192

It took some mucking about (modifying ubi-partman so that calculate_reuse_option was called when there are 3 operating systems and in that function setting final to True (since Trusty is not final)) but I was able to test this situation. I choose to reinstall Ubuntu 14.04 and lose all my 14.04 settings and documents. This worked exactly as expected and my 14.04 installation was blown away but I was still able to boot into Windows 7 or whatever it is and my grub menu was unchanged.