[HTMLCollection-supported-property-indices.html]
  type: testharness
  [Trying to set an expando that would shadow an already-existing indexed property]
    expected: FAIL

  [Trying to set an expando with an indexed property name past the end of the list]
    expected: FAIL

  [Handling of property names that look like integers around 2^32]
    expected: FAIL

  [Handling of property names that look like integers around 2^31]
    expected: FAIL