MethodOptions.uninterpreted_option difference with protoc if {}

[bufdev]

I could have sworn we dealt with this, but I can't find the issue.

Example:

service Foo {
  rpc Bar(Empty) returns (Empty);
  rpc Baz(Empty) returns (Empty) {}
}

Bar will return the same value for MethodOptions.uninterpreted_option in both protoc and goprotoc, but Baz will have an empty non-nil array in goprotoc, and a nil array in protoc.

This is whatever the opposite of important is, but is getting in the way of automated protoc vs goprotoc testing with proto.Equal unfortunately.

I really thought we dealt with {} vs ;, maybe this is a "regression" ie 3.9.0 is doing something different (the above was done with protoc 3.9.0). EDIT: Also done with protoc 3.7.1, happens with 3.7.1 as well.