title: Angular Fixture DebugElement Query By class Not Returning Elements
body: <p>As suggested by Angular.io Framework Testing documentation, I have been attempting to make use of DebugElement query using Angular Testbed + Karma test Runner.  I have created a jqwidgets Tree component that produces li elements of class '.jqx-tree-item-li'.  The following test using straight javascript on the DOM test passes <strong>GREEN</strong>:</p>
  
  <pre><code>    it('Elements of class jqx-tree-item-li found using getElementsByClassName ', (done) =&gt; {
  
      this.fixture.whenStable().then(
        () =&gt; {
          var elementArray = document.getElementsByClassName('jqx-tree-item-li');
          expect(elementArray.length).toBeGreaterThan(0); //passes without issue :)
          done();
        }
      );
    });
  </code></pre>
  
  <p>But this test in the <strong>SAME</strong> spec (identical Testbed setup) <strong>FAILS</strong> due to 0 elements returned:</p>
  
  <pre><code>   it('Elements of class jqx-tree-item-li found using Angular DebugElement ', (done) =&gt; {
  
      this.fixture.whenStable().then(
        () =&gt; {
          var elementArray = this.fixture.debugElement.queryAll(By.css('.jqx-tree-item-li'));
          expect(elementArray.length).toBeGreaterThan(0); //fails! why? :(
          done();
        }
      );
    });
  </code></pre>
  
  <blockquote>
    <p>Object Explorer Component Elements of class jqx-tree-item-li found using Angular 
    DebugElement Expected 0 to be greater than 0.</p>
  </blockquote>
  
  <p>Not the first time I have observed this and I have found that it will get root component elements, but I can't seem to get the DebugElement query to return elements within the component.  Though the documentation states explicitly it will query the subtree.  To date the work around has been just to javascript query like above which does function as intended.</p>
  
  <p>Am I missing something here? Any suggestions on how to get DebugElement.query to work? If not, has anyone found issues with DebugElement query?  Thank you.</p>