Removing an image that fails, also removes the image name/tag.

Fixes #7845 and #7801, and a real pain point I had :)

Docker-DCO-1.1-Signed-off-by: Jessica Frazelle <jess@docker.com> (github: jfrazelle)
I am not sure if this is the right logic here, but I am trying to see if they are just removing an image "tag" or removing the whole image, basically I want to know up here if it will make it to line #108