Bug 2001015 [wpt PR 56108] - Add new tests for customelementregistry content attribute and specifying null to createEleent and attachShadow per, a=testonly

Automatic update from web-platform-tests
Add new tests for customelementregistry content attribute and specifying null to createEleent and attachShadow per (#56108)

- whatwg/dom#1424
- whatwg/dom#1423

Also update the existing tests to account for the behavior differences.`
--

wpt-commits: cc1c056521abd0ff97456455dbebe113617a2bc1
wpt-pr: 56108

UltraBlame original commit: bb6f215085587911288d0b50256c14ad6ecd246e

Author: marco-c

testing/web-platform/tests/custom-elements/registries/Element-customElementRegistry-exceptions.html

@@ -102,84 +102,6 @@
 body
 >
 <
-div
-id
-=
-"
-host
--
-window
-"
->
-<
-template
-shadowrootmode
-=
-"
-open
-"
->
-<
-a
--
-b
->
-<
-/
-a
--
-b
->
-<
-/
-template
->
-<
-/
-div
->
-<
-div
-id
-=
-"
-host
--
-null
-"
->
-<
-template
-shadowrootmode
-=
-"
-open
-"
-shadowrootcustomelementregistry
-=
-"
-"
->
-<
-a
--
-b
->
-<
-/
-a
--
-b
->
-<
-/
-template
->
-<
-/
-div
->
-<
 script
 >
 setup

testing/web-platform/tests/custom-elements/registries/Element-customElementRegistry.html

@@ -523,9 +523,7 @@
 ab
 .
 customElementRegistry
-window
-.
-customElements
+null
 )
 ;
 const

testing/web-platform/tests/custom-elements/registries/ShadowRoot-init-customElementRegistry.html

@@ -426,9 +426,7 @@
 shadowRoot
 .
 customElementRegistry
-window
-.
-customElements
+null
 )
 ;
 }
@@ -438,8 +436,7 @@
 )
 should
 use
-the
-global
+null
 registry
 when
 customElementRegistry
@@ -515,9 +512,7 @@
 shadowRoot
 .
 customElementRegistry
-window
-.
-customElements
+null
 )
 ;
 }
@@ -527,8 +522,7 @@
 )
 should
 use
-the
-global
+null
 registry
 when
 customElementRegistry