In my stupidity, I hastily followed someone's recommendation to fix a printing problem (which I will post in a minute). This person suggested that to fix a cups-pdf problem, one should remove all cups stuff and then just reinstall cups-pdf. After having done this not only did cups-pdf not work but the envince document viewer (the default ubuntu pdf reader) was gone, plus a bunch of other cups packages.

Apparently, if you accidentally remove default packages in the desktop version, you can restore them as easy as:
sudo apt-get install ubuntu-desktop

Hopefully someone will find this helpful.