PASS node.element.firstElementChild.nextElementSibling === b.element is true
PASS node.element.lastElementChild === c.element is true
+Set children to be a copy of itself
+PASS node.children[0].needsLayout is false
+PASS node.children[1].needsLayout is false
+PASS node.children[2].needsLayout is false
+
Set children to [b, a]
PASS node.children.length === 2 is true
PASS node.children[0] === b is true