[texture-copying-feedback-loops.html]
  bug: https://github.com/servo/servo/issues/21288
  [WebGL test #3: getError expected: INVALID_OPERATION. Was NO_ERROR : after copyTexImage2D to same texture same level, invalid feedback loop]
    expected: FAIL

  [WebGL test #6: getError expected: INVALID_OPERATION. Was NO_ERROR : after copyTexSubImage2D to same texture same level, invalid feedback loop]
    expected: FAIL