Add private click measurement (#2467)

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

features/private-click-measurement.yml

@@ -0,0 +1,6 @@
+name: Private click measurement
+description: The `attributionsourceid` and `attributiondestination` attributes for `<a>` elements measure clicks across websites without associating a click to a specific session. Not to be confused with attribution reporting. Also known as PCM.
+spec: https://privacycg.github.io/private-click-measurement/
+compat_features:
+  - api.HTMLAnchorElement.attributionSourceId
+  - html.elements.a.attributionsourceid

features/private-click-measurement.yml.dist

@@ -0,0 +1,21 @@
+# Generated from: private-click-measurement.yml
+# Do not edit this file by hand. Edit the source file instead!
+
+status:
+  baseline: false
+  support:
+    safari: "15.4"
+    safari_ios: "15.4"
+compat_features:
+  # baseline: false
+  # support:
+  #   safari: "14.1"
+  #   safari_ios: "14.5"
+  - html.elements.a.attributionsourceid
+
+  # ⬇️ Same status as overall feature ⬇️
+  # baseline: false
+  # support:
+  #   safari: "15.4"
+  #   safari_ios: "15.4"
+  - api.HTMLAnchorElement.attributionSourceId