title: Object.assign() vs. angular.extend()
body: <p>Is there any difference in behavior between the angularjs <code>angular.extend(src, dst)</code> and the javascript <code>Object.assign(src, dst)</code> functions?</p>
  
  <p>Using the test from <a href="https://stackoverflow.com/a/36828514">https://stackoverflow.com/a/36828514</a>, they both seem identical.</p>
  
  <p>If they really are, is there any difference in performance? What are pros and cons for using one over the other?</p>