'No pictures are available on the phone' after selecting contact picture

After upgrading my Nexus 5 to vanilla Lollipop a few days ago, I'm no longer able to assign pictures to my contacts. I can tap "Choose photo" and select a picture, but when I confirm I get the error "No pictures are available on the phone". How can this happen? It doesn't make any sense. I already tried wiping cache from recovery because some people say that it can fix some upgrade problems, but that didn't solve anything for me.