ReadonlyLABEL_0 is reserved for errors
ReadonlyLABEL_Represents the LABEL_REPEATED protobuf enum value.
ReadonlyLABEL_The required label is only allowed in google.protobuf. In proto3 and Editions
it's explicitly prohibited. In Editions, the field_presence feature
can be used to get this behavior.
Defines the static values of FieldDescriptorProto_Label.