BabelJS Bug

BabelBug.js

//Expected output: A B C  (see http://www.es6fiddle.net/ice1qchm/)
//Actual output from Babel: A C

//ES5 legacy code

function A () {
  console.log("A");
}

function B () {
    A.call(this);
    console.log("B");
}

B.prototype = Object.create(A.prototype);
B.constructor = B;

//ES6 code

class C extends B {
    constructor(data) {
        super({}); //Should call B(), no?
        console.log("C");
    }
}

new C();