title: Get element by binding for 'ng-src' not working, Protractor
body: <p>In Angular Phone cat application (step-10), I am not able to use <code>element(by.binding('bindingName'))</code>   <a href="https://github.com/angular/protractor/blob/master/docs/locators.md#locators" rel="nofollow">Protractor locators</a></p>
  
  <p><strong>Tutorial link</strong>: <a href="https://docs.angularjs.org/tutorial/step_10/#test" rel="nofollow">Angular phone cat app (step-10, test)</a></p>
  
  <p><strong>Details</strong>:</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>// Working
  expect(element(by.css('img.phone')).getAttribute('src'))
    .toMatch(/img\/phones\/nexus-s.0.jpg/);
  
  // Not Working
  expect(element(by.binding('mainImageUrl')).getAttribute('src'))
    .toMatch(/img\/phones\/nexus-s.0.jpg/);</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;img ng-src="{{mainImageUrl}}" class="phone"&gt;</code></pre>
  </div>
  </div>
  </p>