code: static JbcSrcJavaValue of(
        SoyExpression expr, SoyType allowedType, JbcSrcValueErrorReporter reporter) {
      return new JbcSrcJavaValue(
          expr,
          /* method= */ null,
          checkNotNull(allowedType),
          /* constantNull= */ false,
          /* error= */ false,
          reporter);
    }
docs: Constructs a JbcSrcJavaValue based on the Expression, with the given SoyType as allowed types.
  The SoyType is expected to be based on the function signature, so can be broader than the soy
  type of the expression itself. The expression is expected to be assignable to the type.