As noted by #30083, the new strict checking of mediatypes misses some cases where earlier bugs caused nonstandard mediatypes to be stored in manifests. Two of the known cases are text/html and application/json, which were returned by certain registries and stored by earlier versions of Docker. Add special cases for text/html and application/json. Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com> Upstream-commit: a215e15cb1fbecc3b22d4f90e15638728ac7ac78 Component: engine