code: public static Protos.Resource scalar(String name, String role, double value) {
  		checkNotNull(name);
  		checkNotNull(role);
  		checkNotNull(value);
  		return Protos.Resource.newBuilder()
  			.setName(name)
  			.setType(Protos.Value.Type.SCALAR)
  			.setScalar(Protos.Value.Scalar.newBuilder().setValue(value))
  			.setRole(role)
  			.build();
  	}
docs: Construct a scalar resource.