Auto merge of #26953 - mrobinson:cancel-reparent, r=nox

Cancel animations for nodes which are removed from the DOM

This includes nodes which are being reparented.

---
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] There are tests for these changes

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tests/wpt/metadata-layout-2020/css/css-transitions/disconnected-element-001.html.ini

@@ -1,8 +0,0 @@
-[disconnected-element-001.html]
-  expected: TIMEOUT
-  [Transitions are canceled when an element is re-parented to the same node]
-    expected: NOTRUN
-
-  [Transitions are canceled when an element is re-parented]
-    expected: TIMEOUT
-

tests/wpt/metadata-layout-2020/css/css-transitions/properties-value-001.html.ini

@@ -212,9 +212,6 @@
   [text-indent length(in) / events]
     expected: FAIL
 
-  [visibility visibility(keyword) / events]
-    expected: FAIL
-
   [text-indent length(pc) / events]
     expected: FAIL
 
@@ -227,9 +224,6 @@
   [text-indent length(cm) / events]
     expected: FAIL
 
-  [visibility visibility(keyword) / values]
-    expected: FAIL
-
   [outline-width length(cm) / events]
     expected: FAIL
 

tests/wpt/metadata-layout-2020/css/css-transitions/properties-value-inherit-001.html.ini

@@ -104,9 +104,6 @@
   [vertical-align length(cm) / values]
     expected: FAIL
 
-  [visibility visibility(keyword) / events]
-    expected: FAIL
-
   [vertical-align length(ex) / values]
     expected: FAIL
 

tests/wpt/metadata-layout-2020/css/css-transitions/properties-value-inherit-002.html.ini

@@ -212,9 +212,6 @@
   [text-indent length(in) / events]
     expected: FAIL
 
-  [visibility visibility(keyword) / events]
-    expected: FAIL
-
   [text-indent length(pc) / events]
     expected: FAIL
 
@@ -227,9 +224,6 @@
   [text-indent length(cm) / events]
     expected: FAIL
 
-  [visibility visibility(keyword) / values]
-    expected: FAIL
-
   [outline-width length(cm) / events]
     expected: FAIL
 

tests/wpt/metadata/css/css-transitions/disconnected-element-001.html.ini

@@ -1,8 +0,0 @@
-[disconnected-element-001.html]
-  expected: TIMEOUT
-  [Transitions are canceled when an element is re-parented to the same node]
-    expected: NOTRUN
-
-  [Transitions are canceled when an element is re-parented]
-    expected: TIMEOUT
-