code: function (fullName) {
        _emberMetalDebug.assert('fullName must be a proper full name', this.validateFullName(fullName));
  
        var normalizedName = this.normalize(fullName);
  
        this._localLookupCache = new _emberMetalEmpty_object.default();
  
        delete this.registrations[normalizedName];
        delete this._resolveCache[normalizedName];
        delete this._failCache[normalizedName];
        delete this._options[normalizedName];
      }
docs: Unregister a fullName
  ```javascript
  var registry = new Registry();
  registry.register('model:user', User);
  registry.resolve('model:user').create() instanceof User //=> true
  registry.unregister('model:user')
  registry.resolve('model:user') === undefined //=> true
  ```
  @private
  @method unregister
  @param {String} fullName