const google.golang.org/protobuf/internal/genid.FieldDescriptorProto_OneofIndex_field_fullname

one use

	google.golang.org/protobuf/internal/genid (current package)
		descriptor_gen.go#L219: 	FieldDescriptorProto_OneofIndex_field_fullname     protoreflect.FullName = "google.protobuf.FieldDescriptorProto.oneof_index"