Multibyte characters on chunk boundaries get corrupted.

test/specs/core/mergeConfig.spec.js
var defaults = require('../../../lib/defaults');
var mergeConfig = require('../../../lib/core/mergeConfig');
describe('core::mergeConfig', function() {
  it('should accept undefined for second argument', function() {
    expect(mergeConfig(defaults, undefined)).toEqual(defaults);
  });
  it('should accept an object for second argument', function() {
    expect(mergeConfig(defaults, {})).toEqual(defaults);
  });
  it('should not leave references', function() {
    var merged = mergeConfig(defaults, {});