code: function deprecateProperty(object, deprecatedKey, newKey) {
        function deprecate() {
          Ember.deprecate('Usage of `' + deprecatedKey + '` is deprecated, use `' + newKey + '` instead.');
        }
  
        if (hasPropertyAccessors) {
          defineProperty(object, deprecatedKey, {
              configurable: true,
              enumerable: false,
              set: function(value) { deprecate(); set(this, newKey, value); },
              get: function() { deprecate(); return get(this, newKey); }
          });
        }
      }
docs: Used internally to allow changing properties in a backwards compatible way, and print a helpful
  deprecation warning.
  
  @method deprecateProperty
  @param {Object} object The object to add the deprecated property to.
  @param {String} deprecatedKey The property to add (and print deprecation warnings upon accessing).
  @param {String} newKey The property that will be aliased.
  @private
  @since 1.7.0