When using Gorilla's compress handler, don't use WriteHeader without content type.
When using Gorilla's compress handler, don't use WriteHeader without content type.

Since Gorilla is compressing everything, don't call WriteHeader with a body
unless a content type is set.  Otherwise, the system overrides the content
type with gzip, which some browsers get upset over.

This showed up in integration stuff, but it is something to keep in mind for
the future.

CCJ16/registration,CCJ16/registration,CCJ16/registration