Unable to make class generic with JSDoc

**TypeScript Version:**  2.6.0-dev.20170829

```js
/**
 * @template T
 */
class MyArray {
  constructor() {
    /** @type {Array<T>} */
    this.array = [];
  }
}
/** @type {MyArray<string>} */
let x = new MyArray();
```

**Expected behavior:**
`x` should contain an array of strings.

**Actual behavior:**
`[js] Cannot find name 'T'.`
`[js] Type 'MyArray' is not generic.`
