|  | <!DOCTYPE html> | 
|  | <meta name="viewport" content="width=device-width,initial-scale=1"> | 
|  | <script src="/resources/testharness.js"></script> | 
|  | <script src="/resources/testharnessreport.js"></script> | 
|  | <script src="./resources/intersection-observer-test-utils.js"></script> | 
|  |  | 
|  | <style> | 
|  | pre, #log { | 
|  | position: absolute; | 
|  | top: 0; | 
|  | left: 200px; | 
|  | } | 
|  | iframe { | 
|  | height: 250px; | 
|  | width: 150px; | 
|  | border: 0; | 
|  | } | 
|  | </style> | 
|  | <iframe id="target-iframe" src="resources/iframe-no-root-subframe.html"></iframe> | 
|  |  | 
|  | <script> | 
|  | var iframe = document.getElementById("target-iframe"); | 
|  | var target; | 
|  | var root; | 
|  | var entries = []; | 
|  |  | 
|  | iframe.onload = function() { | 
|  | runTestCycle(function() { | 
|  | assert_true(!!iframe, "iframe exists"); | 
|  |  | 
|  | target = iframe.contentDocument.getElementById("target"); | 
|  | assert_true(!!target, "Target element exists."); | 
|  | var observer = new IntersectionObserver(function(changes) { | 
|  | entries = entries.concat(changes) | 
|  | }, { root: iframe.contentDocument }); | 
|  | observer.observe(target); | 
|  | entries = entries.concat(observer.takeRecords()); | 
|  | assert_equals(entries.length, 0, "No initial notifications."); | 
|  | runTestCycle(step0, "First rAF."); | 
|  | }, "Observer with explicit root which is the document."); | 
|  | }; | 
|  |  | 
|  | function step0() { | 
|  | let vw = iframe.contentDocument.documentElement.clientWidth; | 
|  | let vh = iframe.contentDocument.documentElement.clientHeight; | 
|  | // The target element is partially clipped by the iframe's root scroller, so | 
|  | // height of the intersection rect is (250 - 208) == 42. | 
|  | checkLastEntry(entries, 0, [8, 108, 208, 308, 8, 108, 208, 250, 0, vw, 0, vh, true]); | 
|  | } | 
|  | </script> |