Description
Is your feature request related to a problem? Please describe.
The current protoc-gen-go/descriptor/descriptor.proto is older than the latest released `original one (https://github.com/protocolbuffers/protobuf/blob/master/src/google/protobuf/descriptor.proto).
2 file options (php_metadata_namespace and ruby_package) are newly added, but these are not available from Go code.
Describe the solution you'd like
make regenerate with the latest protoc (3.6.1).
Then, make a new release.
Describe alternatives you've considered
Ask users to ignore new options.
Additional context
The protoc-gen-go/descriptor/descriptor.pb.go is widely referenced by protobuf related tools written in Go. Some useful tools like grpcurl and evans fail to parse proto files containing the newly added options since the Go descriptor package doesn't know the options.
It would be possible to ignore unknown options on parsers, but I believe keep the proto generated files up to date is better.