This is a testharness.js-based test.
[FAIL] flexbox > item 1
  assert_equals: \n<item data-expected-margin-left="0" data-offset-x="8"></item>\noffsetLeft expected 8 but got 28
[FAIL] flexbox > item 2
  assert_equals: \n<item data-expected-margin-left="20" data-offset-x="78"></item>\noffsetLeft expected 78 but got 98
[FAIL] flexbox > item 3
  assert_equals: \n<item data-expected-margin-left="20" data-offset-x="148"></item>\noffsetLeft expected 148 but got 168
Harness: the test ran to completion.