Add the referencetarget feature (#3376)

Co-authored-by: Daniel D. Beck <[email protected]>

Author: captainbrosset

features/referencetarget.yml

@@ -0,0 +1,10 @@
+name: Reference target
+description: The `referenceTarget` property of a `ShadowRoot` object forwards attributes such as `for` and `aria-labelledby` to elements inside a shadow DOM. You can use this to, for example, link a `<label>` to its `<input>` even if the `<input>` is in the shadow DOM of a web component.
+spec:
+  - https://github.com/whatwg/dom/pull/1353
+  - https://github.com/whatwg/html/pull/10995
+group:
+  - web-components
+# Expected keys via Chrome origin trial in 133-135 https://chromestatus.com/feature/5188237101891584
+# api.Element.attachShadow.options_referenceTarget_parameter
+# api.ShadowRoot.referenceTarget

features/referencetarget.yml.dist

@@ -0,0 +1,6 @@
+# Generated from: referencetarget.yml
+# Do not edit this file by hand. Edit the source file instead!
+
+status:
+  baseline: false
+  support: {}

scripts/specs.ts

@@ -134,6 +134,14 @@ const defaultAllowlist: allowlistItem[] = [
         "https://www.w3.org/TR/2022/WD-selectors-4-20220507/#the-target-within-pseudo",
         "Allowed because this is where the feature last appeared in the spec before removal."
     ],
+    [
+        "https://github.com/whatwg/dom/pull/1353",
+        "Allowed because this is where the referencetarget feature is being added to the DOM spec"
+    ],
+    [
+        "https://github.com/whatwg/html/pull/10995",
+        "Allowed because this is where the referencetarget feature is being added to the HTML spec"
+    ],
     [
         "https://patcg-individual-drafts.github.io/topics/",
         "Allowed because the Topics API isn't on a standards track yet. Remove this exception when it is."