Treat video elements as replaced content and render the current frame.

[jdm]

These changes allow videos that autoplay to render as expected in Layout 2020. Both legacy layout and layout 2020 do not render any video frames when the videos are paused initially, which can be addressed separately.

---

• ./mach build -d does not report any errors
• ./mach test-tidy does not report any errors
• These changes fix Attempt to display inline video fails with Unsupported property declaration: '1280', OtherInvalidValue("width") etc #31208
• There are tests for these changes

[github-actions]

🔨 Triggering try run (#8014569001) for Linux WPT, MacOS, Windows, Android

[github-actions]

🔨 Triggering try run (#8014634018) for Linux WPT

[github-actions]

Test results for linux-wpt-layout-2020 from try job (#8014634018):

Flaky unexpected result (15)

• TIMEOUT [expected OK] /_webgl/conformance/glsl/misc/shader-with-non-reserved-words.html (#16216)
  • NOTRUN [expected PASS] subtest: Overall test
• TIMEOUT [expected OK] /_webgl/conformance/uniforms/out-of-bounds-uniform-array-access.html (#26225)
  • NOTRUN [expected PASS] subtest: Overall test
• TIMEOUT [expected FAIL] /css/css-animations/animation-delay-010.html (#26573)
• TIMEOUT [expected PASS] /css/css-fonts/font-size-adjust-reload.html (#30678)
• OK /css/css-fonts/variations/at-font-face-font-matching.html (#20684)
  • PASS [expected FAIL] subtest: Matching font-weight: '430' should prefer '350 399' over '340 398'
  • PASS [expected FAIL] subtest: Matching font-stretch: '100%' should prefer '110% 120%' over '115% 116%'
  • PASS [expected FAIL] subtest: Matching font-style: 'italic' should prefer 'oblique 20deg' over 'oblique 30deg 60deg'
  • PASS [expected FAIL] subtest: Matching font-style: 'oblique 10deg' should prefer 'oblique 10deg' over 'oblique 5deg'
  • PASS [expected FAIL] subtest: Matching font-style: 'oblique -21deg' should prefer 'italic' over 'oblique 0deg'
• TIMEOUT [expected OK] /html/browsers/browsing-the-web/navigating-across-documents/javascript-url-referrer.window.html (#29081)
  • TIMEOUT [expected PASS] subtest: no-referrer referrer policy used to create the starting page Test timed out
• CRASH [expected OK] /html/browsers/browsing-the-web/unloading-documents/prompt-and-unload-script-closeable.html
• TIMEOUT [expected OK] /html/interaction/focus/the-autofocus-attribute/document-with-fragment-top.html (#28259)
  • TIMEOUT [expected FAIL] subtest: Autofocus elements in top-level browsing context's documents with "top" fragments should work. Test timed out
• CRASH [expected OK] /html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_escaping-3.html (#24057)
• OK /html/semantics/forms/form-submission-0/text-plain.window.html (#28687)
  • PASS [expected FAIL] subtest: text/plain: 0x00 in name (formdata event)
• TIMEOUT [expected OK] /html/semantics/links/links-created-by-a-and-area-elements/htmlanchorelement_noopener.html (#23205)
  • NOTRUN [expected FAIL] subtest: Check that rel=noopener with target=_self does a normal load
  • NOTRUN [expected FAIL] subtest: Check that rel=noopener with target=_parent does a normal load
  • NOTRUN [expected FAIL] subtest: Check that rel=noopener with target=_top does a normal load
• OK /html/semantics/scripting-1/the-script-element/execution-timing/077.html (#22139)
  • FAIL [expected PASS] subtest: adding several types of scripts through the DOM and removing some of them confuses scheduler assert_array_equals: expected property 1 to be "Script Create azure bindings for Rust #1 ran" but got "Script Handle "close window" event and interrupt signal #3 ran" (expected array ["Script Fix out-of-tree builds #2 ran", "Script Create azure bindings for Rust #1 ran", "Script Handle "close window" event and interrupt signal #3 ran", "Script Bind harfbuzz #4 ran"] got ["Script Fix out-of-tree builds #2 ran", "Script Handle "close window" event and interrupt signal #3 ran", "Script Bind harfbuzz #4 ran", "Script Create azure bindings for Rust #1 ran"])
• TIMEOUT /html/webappapis/scripting/events/compile-event-handler-settings-objects.html (#24246)
  • PASS [expected FAIL] subtest: The entry settings object while executing the compiled callback via Web IDL's invoke must be that of the node document
• OK [expected TIMEOUT] /webmessaging/with-ports/018.html (#24485)
  • PASS [expected TIMEOUT] subtest: origin of the script that invoked the method, javascript:
• TIMEOUT [expected OK] /webmessaging/without-ports/017.html (#24486)
  • TIMEOUT [expected PASS] subtest: origin of the script that invoked the method, about:blank Test timed out

Stable unexpected results that are known to be intermittent (17)

• TIMEOUT [expected OK] /_webgl/conformance/glsl/misc/shader-uniform-packing-restrictions.html (#28103)
  • NOTRUN [expected PASS] subtest: Overall test
• TIMEOUT /fetch/metadata/generated/element-img-environment-change.sub.html (#30111)
  • PASS [expected FAIL] subtest: sec-fetch-site - Not sent to non-trustworthy same-origin destination, no attributes
• OK /html/browsers/browsing-the-web/navigating-across-documents/empty-iframe-load-event.html (#29066)
  • FAIL [expected PASS] subtest: Check execution order from nested timeout assert_equals: Expected nested setTimeout to run second expected true but got false
  • FAIL [expected PASS] subtest: Check execution order on load handler assert_equals: Expected onload to run first expected false but got true
• OK /html/browsers/browsing-the-web/navigating-across-documents/initial-empty-document/load-pageshow-events-iframe-contentWindow.html (#28681)
  • PASS [expected FAIL] subtest: load & pageshow events do not fire on contentWindow of <iframe> element created with src='about:blank'
• OK /html/browsers/browsing-the-web/navigating-across-documents/initial-empty-document/load-pageshow-events-window-open.html (#28691)
  • FAIL [expected PASS] subtest: load event does not fire on window.open('about:blank') assert_unreached: load should not be fired Reached unreachable code
• OK /html/browsers/browsing-the-web/navigating-across-documents/javascript-url-return-value-handling-dynamic.html (#28066)
  • FAIL [expected PASS] subtest: 0041 set in href="" targeting a frame and clicked assert_equals: expected "A" but got ""
• OK /html/browsers/browsing-the-web/navigating-across-documents/navigation-unload-cross-origin.sub.window.html (#29056)
  • PASS [expected FAIL] subtest: Cross-origin navigation started from unload handler must be ignored
• OK /html/browsers/history/the-history-interface/traverse_the_history_5.html (#21383)
  • PASS [expected FAIL] subtest: Multiple history traversals, last would be aborted
• OK /html/browsers/the-window-object/open-close/creating_browsing_context_test_01.html (#29046)
  • PASS [expected FAIL] subtest: first argument: absolute url
• OK [expected TIMEOUT] /html/interaction/focus/the-autofocus-attribute/supported-elements.html (#24145)
  • FAIL [expected TIMEOUT] subtest: Host element with delegatesFocus including no focusable descendants should be skipped promise_test: Unhandled rejection with value: object "TypeError: host.attachShadow is not a function"
  • FAIL [expected NOTRUN] subtest: Area element should support autofocus assert_equals: expected Element node <area></area> but got Element node <body>
    <img src="/media/poster.png" usemap="#map">
    <map n...
• OK [expected TIMEOUT] /html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_escaping-1.html (#22647)
  • FAIL [expected TIMEOUT] subtest: Check that popups from a sandboxed iframe escape the sandbox if
    allow-popups-to-escape-sandbox is used assert_equals: It came from a sandboxed iframe expected "null" but got "http://web-platform.test:8000"
• OK [expected TIMEOUT] /html/semantics/embedded-content/the-iframe-element/iframe_sandbox_popups_nonescaping-1.html (#24066)
  • FAIL [expected NOTRUN] subtest: Check that popups from a sandboxed iframe do not escape the sandbox assert_equals: It came from a sandboxed iframe expected "null" but got "http://web-platform.test:8000"
• OK /html/semantics/forms/historical.html (#28568)
  • FAIL [expected PASS] subtest: <input name=isindex> should not be supported assert_regexp_match: expected object "/?isindex=x$/" but got "about:blank"
• OK [expected ERROR] /html/semantics/scripting-1/the-script-element/defer-script/async-script.html?reload (#29054)
• TIMEOUT /resource-timing/test_resource_timing.html (#25720)
  • PASS [expected FAIL] subtest: PerformanceEntry has correct name, initiatorType, startTime, and duration (img)
• TIMEOUT /resource-timing/test_resource_timing.https.html (#25216)
  • FAIL [expected PASS] subtest: PerformanceEntry has correct name, initiatorType, startTime, and duration (img) assert_equals: expected 21389824 but got 21390080
• TIMEOUT [expected OK] /webmessaging/without-ports/018.html (#24485)
  • TIMEOUT [expected PASS] subtest: origin of the script that invoked the method, javascript: Test timed out

Stable unexpected results (4)

• FAIL [expected PASS] /css/css-images/object-view-box-fit-cover-video.html
• FAIL [expected PASS] /css/css-images/object-view-box-writing-mode-video.html
• PASS [expected FAIL] /html/semantics/embedded-content/the-video-element/video_dynamic_poster_absolute.htm
• PASS [expected FAIL] /html/semantics/embedded-content/the-video-element/video_dynamic_poster_relative.htm

[github-actions]

⚠️ Try run (#8014634018) failed.