message: protobuf util: Correct name for RepeatedPtrField
  Use `Protobuf::RepeatedPtrField<>` as the argument type for `hash()` for consistency.
diff: @@ -72,7 +72,7 @@ public:
  // Based on MessageUtil::hash() defined below.
  template <class ProtoType>
  - static std::size_t hash(const google::protobuf::RepeatedPtrField<ProtoType>& source) {
  + static std::size_t hash(const Protobuf::RepeatedPtrField<ProtoType>& source) {
  // Use Protobuf::io::CodedOutputStream to force deterministic serialization, so that the same
  // message doesn't hash to different values.
  ProtobufTypes::String text;
  