message: Indent auto-generated build method
  TESTED manually
diff: @@ -384,7 +384,8 @@ void OpEmitter::emitBuilder() {
  // Attributes
  if (attrs.empty()) {
  - os << " assert(!attributes.size() && \"no attributes expected\");\n}\n";
  + os << " assert(!attributes.size() && \"no attributes expected\");\n"
  + << " }\n";
  } else {
  os << " assert(attributes.size() >= " << attrs.size()
  << "u && \"not enough attributes\");\n"
  