IntersectionObserver: convert tests to testharness.js

third_party/WebKit/LayoutTests/http/tests/intersection-observer/iframe-cross-origin-expected.txt

-Simple intersection observer test with no explicit root and target in a cross-origin iframe.
-
-On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
-
-
-PASS actual.length is 0
-PASS actual.length is 0
-PASS actual.length is 1
-PASS actual.boundingClientRect.left is 8
-PASS actual.boundingClientRect.top is -42
-PASS actual.boundingClientRect.right is 108
-PASS actual.boundingClientRect.bottom is 58
-PASS actual.boundingClientRect.width is 100
-PASS actual.boundingClientRect.height is 100
-PASS actual.intersectionRect.left is 8
-PASS actual.intersectionRect.top is 0
-PASS actual.intersectionRect.right is 108
-PASS actual.intersectionRect.bottom is 58
-PASS actual.intersectionRect.width is 100
-PASS actual.intersectionRect.height is 58
-PASS actual.rootBounds is null
-PASS actual.target is "target"
-PASS actual.length is 1
-PASS actual.boundingClientRect.left is 8
-PASS actual.boundingClientRect.top is -42
-PASS actual.boundingClientRect.right is 108
-PASS actual.boundingClientRect.bottom is 58
-PASS actual.boundingClientRect.width is 100
-PASS actual.boundingClientRect.height is 100
-PASS actual.intersectionRect.left is 0
-PASS actual.intersectionRect.top is 0
-PASS actual.intersectionRect.right is 0
-PASS actual.intersectionRect.bottom is 0
-PASS actual.intersectionRect.width is 0
-PASS actual.intersectionRect.height is 0
-PASS actual.rootBounds is null
-PASS actual.target is "target"
-PASS successfullyParsed is true
-
-TEST COMPLETE
-
-