[start.dedicatedworker.html]
  type: testharness
  [underlying sink's write should not be called until start finishes]
    expected: FAIL

  [underlying sink's close should not be called until start finishes]
    expected: FAIL

  [underlying sink's write or close should not be called if start throws]
    expected: FAIL

  [underlying sink's write or close should not be invoked if the promise returned by start is rejected]
    expected: FAIL

  [returning a thenable from start() should work]
    expected: FAIL

