title: this inside an async object method
body: <p>I creating an object that uses async function methods with babel-polyfill/babel-preset-es2017, however I am having a problem with <code>this</code>:</p>
  
  <pre><code>let obj = () =&gt; {
      return {
          doAsync: async () =&gt; {
              let thing = await longProcess()
              return this.transform(thing)
          },
  
          transform: (thing) =&gt; {
              return psuedoCodeTransform(thing)
          }
      }
  }
  
  let instance = obj()
  instance.doAsync()
  // TypeError: cannot read property 'transform' of undefined`.
  </code></pre>
  
  <p>Is this something described in ES2017, a babel-polyfill/regeneratorRuntime gotcha?</p>