Import wpt@9fcccf38b6be00f71ffa6bd6e29c5aa1ef25ee8c

third_party/WebKit/LayoutTests/imported/wpt/custom-elements/resources/custom-elements-helpers.js

 function create_window_in_test(t, srcdoc) {
   let p = new Promise((resolve) => {
     let f = document.createElement('iframe');
     f.srcdoc = srcdoc ? srcdoc : '';
     f.onload = (event) => {
       let w = f.contentWindow;
       t.add_cleanup(() => f.parentNode && f.remove());
       resolve(w);
     };
     document.body.appendChild(f);
   });
   return p;
 }
 
 function test_with_window(f, name, srcdoc) {
   promise_test((t) => {
     return create_window_in_test(t, srcdoc)
     .then((w) => {
-      f(w);
+      f(w, w.document);
     });
   }, name);
 }
 
+function define_custom_element_in_window(window, name, observedAttributes) {
+    let log = [];
+
+    class CustomElement extends window.HTMLElement {
+        constructor() {
+            super();
+            log.push(create_constructor_log(this));
+        }
+        attributeChangedCallback(...args) {
+            log.push(create_attribute_changed_callback_log(this, ...args));
+        }
+        connectedCallback() { log.push(create_connected_callback_log(this)); }
+        disconnectedCallback() { log.push(create_disconnected_callback_log(this)); }
+        adoptedCallback(oldDocument, newDocument) { log.push({type: 'adopted', element: this, oldDocument: oldDocument, newDocument: newDocument}); }
+    }
+    CustomElement.observedAttributes = observedAttributes;
+
+    window.customElements.define(name, CustomElement);
+
+    return {
+        name: name,
+        class: CustomElement,
+        takeLog: function () {
+            let currentLog = log; log = [];
+            currentLog.types = () => currentLog.map((entry) => entry.type);
+            currentLog.last = () => currentLog[currentLog.length - 1];
+            return currentLog;
+        }
+    };
+}
+
+function create_constructor_log(element) {
+    return {type: 'constructed', element: element};
+}
+
+function assert_constructor_log_entry(log, element) {
+    assert_equals(log.type, 'constructed');
+    assert_equals(log.element, element);
+}
+
+function create_connected_callback_log(element) {
+    return {type: 'connected', element: element};
+}
+
+function assert_connected_log_entry(log, element) {
+    assert_equals(log.type, 'connected');
+    assert_equals(log.element, element);
+}
+
+function create_disconnected_callback_log(element) {
+    return {type: 'disconnected', element: element};
+}
+
+function assert_disconnected_log_entry(log, element) {
+    assert_equals(log.type, 'disconnected');
+    assert_equals(log.element, element);
+}
+
 function create_attribute_changed_callback_log(element, name, oldValue, newValue, namespace) {
     return {
         type: 'attributeChanged',
         element: element,
         name: name,
         namespace: namespace,
         oldValue: oldValue,
         newValue: newValue,
         actualValue: element.getAttributeNS(namespace, name)
     };
@@ skipping 120 matching lines @@
                     xhr.overrideMimeType('text/xml');
                     xhr.onload = function () { resolve(xhr.responseXML); }
                     xhr.onerror = function () { reject('Failed to fetch the document'); }
                     xhr.send();
                 });
             },
             hasBrowsingContext: false,
         }
     ];
 }