code: function defineWarningProperty(object, key) {
    Object.defineProperty(object, key, {
  
      configurable: false,
      enumerable: true,
  
      get: function() {
        if (!this._store) {
          return null;
        }
        return this._store[key];
      },
  
      set: function(value) {
        ("production" !== "development" ? warning(
          false,
          'Don\'t set the %s property of the React element. Instead, ' +
          'specify the correct value when initially creating the element.',
          key
        ) : null);
        this._store[key] = value;
      }
  
    });
  }
docs: Warn for mutations.
  
  @internal
  @param {object} object
  @param {string} key