[CustomElementRegistry-initialize.tentative.html]
  [initialize is a function on both global and scoped CustomElementRegistry]
    expected: FAIL

  [initialize sets element.customElements to the global registry]
    expected: FAIL

  [initialize does not set the registry of nested shadow tree to the global registry]
    expected: FAIL

  [initialize sets element.customElements to a scoped registry]
    expected: FAIL

  [initialize does not set the registry of nested shadow tree to a scoped registry]
    expected: FAIL

  [initialize sets element.customElements permantently]
    expected: FAIL

  [initialize is no-op on a subtree with a non-null registry]
    expected: FAIL