old_contents: /**
   * Copyright (c) Facebook, Inc. and its affiliates.
   *
   * This source code is licensed under the MIT license found in the
   * LICENSE file in the root directory of this source tree.
   */
  
  "use strict";
  
  var mergeHelpers = require('mergeHelpers');
  
  var checkMergeObjectArg = mergeHelpers.checkMergeObjectArg;
  var checkMergeIntoObjectArg = mergeHelpers.checkMergeIntoObjectArg;
  
  /**
   * Shallow merges two structures by mutating the first parameter.
   *
   * @param {object|function} one Object to be merged into.
   * @param {?object} two Optional object with properties to merge from.
   */
  function mergeInto(one, two) {
    checkMergeIntoObjectArg(one);
    if (two != null) {
      checkMergeObjectArg(two);
      for (var key in two) {
        if (!two.hasOwnProperty(key)) {
          continue;
        }
        one[key] = two[key];
      }
    }
  }
  
  module.exports = mergeInto;
  
new_contents: /**
   * Copyright (c) Facebook, Inc. and its affiliates.
   *
   * This source code is licensed under the MIT license found in the
   * LICENSE file in the root directory of this source tree.
   */
  
  "use strict";
  
  var mergeHelpers = require('mergeHelpers');
  
  var checkMergeObjectArg = mergeHelpers.checkMergeObjectArg;
  var checkMergeIntoObjectArg = mergeHelpers.checkMergeIntoObjectArg;
  
  /**
   * Shallow merges two structures by mutating the first parameter.
   *
   * @param {object|function} one Object to be merged into.
   * @param {?object} two Optional object with properties to merge from.
   */
  function mergeInto(one, two) {
    checkMergeIntoObjectArg(one);
    if (two != null) {
      checkMergeObjectArg(two);
      for (var key in two) {
        if (!Object.prototype.hasOwnProperty.call(two, key)) {
          continue;
        }
        one[key] = two[key];
      }
    }
  }
  
  module.exports = mergeInto;
  
subject: Fix bug in comparison logic of object property (#22348)