DevTools: migrate inspector-protocol/dom tests to a new test runner

third_party/WebKit/LayoutTests/inspector-protocol/dom/dom-request-child-nodes-traverse-frames.js

+(async function(testRunner) {
+  var {page, session, dp} = await testRunner.startURL('resources/dom-request-child-nodes-traverse-frames.html', '');
+
+  var response = await dp.DOM.getDocument();
+  var rootId = response.result.root.children[0].children[1].nodeId;
+  dp.DOM.requestChildNodes({nodeId: rootId, depth: -1});
+  var message = await dp.DOM.onceSetChildNodes();
+  var iframeContentDocument = message.params.nodes[0].children[0].children[0].children[0].contentDocument;
+  if (iframeContentDocument.children) {
+    testRunner.die("Error IFrame node should not include children: " + JSON.stringify(iframeContentDocument, null, "    "));
+    return;
+  }
+  var message = await dp.DOM.getDocument({pierce: true});
+  var bodyId = message.result.root.children[0].children[1].nodeId;
+  dp.DOM.requestChildNodes({nodeId: bodyId, depth: -1, pierce: true});
+  var message = await dp.DOM.onceSetChildNodes();
+
+  testRunner.logMessage(message);
+  testRunner.completeTest();
+});