title: Cannot import exported interface - export not found
body: <p>I reduced the issue to this example:</p>
  
  <p><strong>test.model.ts</strong></p>
  
  <pre><code>export class A {
      a: number;
  }
  
  export interface B {
      b: number;
  }
  </code></pre>
  
  <p><strong>test.component.ts</strong></p>
  
  <pre><code>import { Component, Input } from '@angular/core';
  import { A, B } from './test.model';
  
  @Component({
      selector: 'test',
      template: '&lt;h1&gt;test&lt;/h1&gt;'
  })
  export class TestComponent {
  
      //This works fine
      @Input() foo: A;
  
      //Does NOT work - export 'B' was not found in './test.model'
      @Input() bar: B;
  
  }
  </code></pre>
  
  <p>When I want to use an <strong>interface</strong> I get following warning:</p>
  
  <pre><code>WARNING in ./src/app/.../test.component.ts
  21:76 export 'B' was not found in './test.model'
  </code></pre>
  
  <p>However, using a <strong>class</strong> is OK. Any hint?</p>
  
  <p><strong>UPDATE</strong>: It seems to be somehow related to this issue: <a href="https://github.com/webpack/webpack/issues/2977" rel="noreferrer">https://github.com/webpack/webpack/issues/2977</a></p>