Implement onremove event for web animations.

Spec:
https://drafts.csswg.org/web-animations-1/#remove-replaced-animations

Intent:
https://groups.google.com/a/chromium.org/forum/#!msg/blink-dev/H5sz_dg6fKc/1X7K7U4XCgAJ

Bug: 981905
Change-Id: I9267e3e4fda14133f2edcc0e8aea1e8a031959a1
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2020245
Commit-Queue: Kevin Ellis <kevers@chromium.org>
Reviewed-by: Robert Flack <flackr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#735437}

third_party/blink/public/mojom/web_feature/web_feature.mojom

@@ -2508,6 +2508,8 @@ enum WebFeature {
   kTaskControllerSetPriority= 3143,
   kTaskSignalPriority = 3144,
   kSchedulerPostTask = 3145,
+  kV8Animation_Onremove_AttributeGetter = 3146,
+  kV8Animation_Onremove_AttributeSetter = 3147,
 
   // Add new features immediately above this line. Don't change assigned
   // numbers of any item, and don't reuse removed slots.

third_party/blink/renderer/core/animation/animation.h

@@ -173,6 +173,7 @@ class CORE_EXPORT Animation : public EventTargetWithInlineData,
 
   DEFINE_ATTRIBUTE_EVENT_LISTENER(finish, kFinish)
   DEFINE_ATTRIBUTE_EVENT_LISTENER(cancel, kCancel)
+  DEFINE_ATTRIBUTE_EVENT_LISTENER(remove, kRemove)
 
   const AtomicString& InterfaceName() const override;
   ExecutionContext* GetExecutionContext() const override;

third_party/blink/renderer/core/animation/animation.idl

@@ -58,6 +58,7 @@ enum ReplaceState { "active", "removed", "persisted" };
     [Measure] void cancel();
     [Measure] attribute EventHandler onfinish;
     [Measure] attribute EventHandler oncancel;
+    [RuntimeEnabled=WebAnimationsAPI, Measure] attribute EventHandler onremove;
     [RuntimeEnabled=WebAnimationsAPI, CallWith=ScriptState] readonly attribute Promise<Animation> finished;
     [RuntimeEnabled=WebAnimationsAPI, CallWith=ScriptState] readonly attribute Promise<Animation> ready;
 };

third_party/blink/web_tests/TestExpectations

@@ -3088,7 +3088,6 @@ crbug.com/967018 external/wpt/html/semantics/scripting-1/the-script-element/css-
 crbug.com/967018 external/wpt/html/semantics/scripting-1/the-script-element/css-module/utf8.tentative.html [ Failure ]
 crbug.com/967018 virtual/web-components-v0-disabled/external/wpt/html/semantics/scripting-1/the-script-element/css-module/utf8.tentative.html [ Failure ]
 crbug.com/626703 external/wpt/css/css-ui/webkit-appearance-auto-001.html [ Failure ]
-crbug.com/626703 external/wpt/web-animations/interfaces/Animation/persist.html [ Timeout ]
 crbug.com/626703 external/wpt/css/css-writing-modes/text-combine-upright-digits-004-manual.html [ Skip ]
 crbug.com/626703 external/wpt/html/semantics/scripting-1/the-script-element/json-module/parse-error.tentative.html [ Timeout ]
 crbug.com/626703 [ Mac10.13 ] external/wpt/preload/onload-event.html [ Failure Timeout ]

third_party/blink/web_tests/external/wpt/web-animations/idlharness.window-expected.txt

 This is a testharness.js-based test.
-Found 143 tests; 137 PASS, 6 FAIL, 0 TIMEOUT, 0 NOTRUN.
+Found 143 tests; 139 PASS, 4 FAIL, 0 TIMEOUT, 0 NOTRUN.
 PASS idl_test setup
 PASS idl_test validation
 PASS Partial interface Document: original interface defined
@@ -57,7 +57,7 @@ PASS Animation interface: attribute ready
 PASS Animation interface: attribute finished
 PASS Animation interface: attribute onfinish
 PASS Animation interface: attribute oncancel
-FAIL Animation interface: attribute onremove assert_true: The prototype object must have a property "onremove" expected true got false
+PASS Animation interface: attribute onremove
 PASS Animation interface: operation cancel()
 PASS Animation interface: operation finish()
 PASS Animation interface: operation play()
@@ -81,7 +81,7 @@ PASS Animation interface: new Animation() must inherit property "ready" with the
 PASS Animation interface: new Animation() must inherit property "finished" with the proper type
 PASS Animation interface: new Animation() must inherit property "onfinish" with the proper type
 PASS Animation interface: new Animation() must inherit property "oncancel" with the proper type
-FAIL Animation interface: new Animation() must inherit property "onremove" with the proper type assert_inherits: property "onremove" not found in prototype chain
+PASS Animation interface: new Animation() must inherit property "onremove" with the proper type
 PASS Animation interface: new Animation() must inherit property "cancel()" with the proper type
 PASS Animation interface: new Animation() must inherit property "finish()" with the proper type
 PASS Animation interface: new Animation() must inherit property "play()" with the proper type

third_party/blink/web_tests/external/wpt/web-animations/interfaces/Animation/onremove.html

+<!DOCTYPE html>
+<meta charset=utf-8>
+<title>Animation.onremove</title>
+<link rel="help" href="https://drafts.csswg.org/web-animations/#dom-animation-onremove">
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="../../testcommon.js"></script>
+<body>
+<div id="log"></div>
+<script>
+'use strict';
+
+async_test(t => {
+  const div = createDiv(t);
+  const animA = div.animate({ opacity: 1 }, { duration: 1, fill: 'forwards' });
+  const animB = div.animate({ opacity: 1 }, { duration: 1, fill: 'forwards' });
+
+  let finishedTimelineTime = null;
+  animB.onfinish = event => {
+    finishedTimelineTime = event.timelineTime;
+  };
+
+  animA.onremove = t.step_func_done(event => {
+    assert_equals(animA.replaceState, 'removed');
+    assert_equals(event.currentTime, 1);
+    assert_true(finishedTimelineTime != null, 'finished event fired');
+    assert_true(event.timelineTime == finishedTimelineTime,
+                'timeline time is set');
+  });
+
+}, 'onremove event is fired when replaced animation is removed.');
+
+promise_test(async t => {
+  const div = createDiv(t);
+  const animA = div.animate({ opacity: 1 }, { duration: 1, fill: 'forwards' });
+  const animB = div.animate({ opacity: 1 }, { duration: 1, fill: 'forwards' });
+  const animC = div.animate({ opacity: 1 }, { duration: 1, fill: 'forwards' });
+  const animD = div.animate({ opacity: 1 }, { duration: 1, fill: 'forwards' });
+
+  const removed = [];
+
+  animA.onremove = () => { removed.push('A'); };
+  animB.onremove = () => { removed.push('B'); };
+  animC.onremove = () => { removed.push('C'); };
+
+  animD.onremove = event => {
+    assert_unreached('onremove event should not be fired');
+  };
+
+  await waitForAnimationFrames(2);
+
+  assert_equals(removed.join(''), 'ABC');
+
+}, 'onremove events are fired in the correct order');
+
+</script>
+</body>
+

third_party/blink/web_tests/external/wpt/web-animations/interfaces/Animation/style-change-events-expected.txt

 This is a testharness.js-based test.
-FAIL All property keys are recognized assert_in_array: Test property 'onremove' should be one of the properties on  Animation value "onremove" not in array ["effect", "startTime", "currentTime", "playbackRate", "playState", "pending", "id", "onfinish", "oncancel", "finish", "play", "pause", "reverse", "updatePlaybackRate", "cancel", "finished", "ready", "replaceState", "timeline", "persist", "Animation constructor"]
+FAIL All property keys are recognized assert_in_array: Test property 'commitStyles' should be one of the properties on  Animation value "commitStyles" not in array ["effect", "startTime", "currentTime", "playbackRate", "playState", "pending", "id", "onfinish", "oncancel", "finish", "play", "pause", "reverse", "updatePlaybackRate", "cancel", "finished", "ready", "replaceState", "timeline", "onremove", "persist", "Animation constructor"]
 PASS Animation.effect produces expected style change events
 PASS Animation.startTime produces expected style change events
 PASS Animation.currentTime produces expected style change events
@@ -19,6 +19,7 @@ PASS Animation.finished produces expected style change events
 PASS Animation.ready produces expected style change events
 PASS Animation.replaceState produces expected style change events
 FAIL Animation.timeline produces expected style change events promise_test: Unhandled rejection with value: object "TypeError: Cannot assign to read only property 'timeline' of object '#<Animation>'"
+PASS Animation.onremove produces expected style change events
 PASS Animation.persist produces expected style change events
 PASS Animation.Animation constructor produces expected style change events
 Harness: the test ran to completion.

third_party/blink/web_tests/webexposed/global-interface-listing-expected.txt

@@ -176,6 +176,7 @@ interface Animation : EventTarget
     getter id
     getter oncancel
     getter onfinish
+    getter onremove
     getter pending
     getter playState
     getter playbackRate
@@ -196,6 +197,7 @@ interface Animation : EventTarget
     setter id
     setter oncancel
     setter onfinish
+    setter onremove
     setter playbackRate
     setter startTime
 interface AnimationEffect

tools/metrics/histograms/enums.xml

@@ -26054,6 +26054,8 @@ to ensure that the crash string is shown properly on the user-facing crash UI.
   <int value="3143" label="TaskControllerSetPriority"/>
   <int value="3144" label="TaskSignalPriority"/>
   <int value="3145" label="SchedulerPostTask"/>
+  <int value="3146" label="V8Animation_Onremove_AttributeGetter"/>
+  <int value="3147" label="V8Animation_Onremove_AttributeSetter"/>
 </enum>
 
 <enum name="FeaturePolicyAllowlistType">