title: TemplateRef constructor injection No provider for TemplateRef
body: <p>Maybe I'm fundamentally misunderstanding something, but I'm trying to get a TemplateRef pointing to my Component's template (simply 'Hello' in the bare-bones example below).  I've stripped my code down to the bare minimum to try to identify the problem:</p>
  
  <pre><code>import { Component, TemplateRef} from '@angular/core';
  @Component({
    selector: 'app-root',
    template: `Hello`,
    styleUrls: ['./app.component.css']
  })
  export class AppComponent implements AfterViewInit {
    constructor(private tr: TemplateRef&lt;any&gt;) {}
  }
  </code></pre>
  
  <p>This doesn't actually "do" anything as I've removed all functionality, but I would have expected this to work.  When I run this code, I get an error: <strong><em>No provider for TemplateRef</em></strong> and yet I see examples on SO and elsewhere where this apparently works.  What am I missing?</p>
  
  <p>Angular 4.2.4</p>
  
  <p>Thanks.</p>