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setup({"hide_test_state": true});
async_test(t => {
assert_implements(window.PerformancePaintTiming, "Paint Timing isn't supported.");
// First observer creates a second one in the callback to ensure the entry has been dispatched
// by the time the second observer begins observing.
new PerformanceObserver(entries => {
const entry_seen = entries.getEntriesByName('first-contentful-paint').length > 0;
// Abort if we have not yet received the entry.
if (!entry_seen)
return;
// Second observer requires 'buffered: true' to see the entry.
new PerformanceObserver(t.step_func_done(list => {
const fcp = list.getEntriesByName('first-contentful-paint');
assert_equals(fcp.length, 1, 'Should have an fcp entry');
const entry = fcp[0];
assert_equals(entry.entryType, 'paint');
})).observe({'type': 'paint', buffered: true});
}).observe({'entryTypes': ['paint']});
// Trigger the first contentful paint entry.
const img = document.createElement("img");
img.src = "../resources/circles.png";
document.body.appendChild(img);
}, "PerformanceObserver with buffered flag sees previous FCP entry.");
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