title: Plain JS or Lodash - replace object values with values from other object
body: <p>I have two objects:</p>
  
  <pre><code>let first = {
     a: 'John',
     b: 22,
     c: 'example'
  }
  
  let second = {
     b: 55,
     d: 'demo'
  }
  </code></pre>
  
  <p>I want to replace only already existing items from second object to first one. Result should look like this (so only b item should be changed, and new d item ignored):</p>
  
  <pre><code>{
     a: 'John',
     b: 55, // changed
     c: 'example'
  }
  </code></pre>
  
  <p>Merge will not work because it will add also new item.
  I can use foreach but I believe that there should be shorted answer for this. I'm already using lodash in my project so I can use function from there, but I cannot find any for this purpose. Is there any?</p>