Update api/ShadowRoot.json

Co-authored-by: Claas Augner <[email protected]>

Author: meyerweb

api/ShadowRoot.json

@@ -738,7 +738,7 @@
             "webview_ios": "mirror"
           },
           "status": {
-            "experimental": false,
+            "experimental": true,
             "standard_track": false,
             "deprecated": false
           }