[DevTools] New harness for inspector-protocol layout tests

third_party/WebKit/LayoutTests/inspector-protocol/stylesheet-tracking-restart.js

+(async function() {
+  InspectorTest.log('This test checks that if style sheet is removed between two inspector launches it is not reported to frontend.');
+  var page = await InspectorTest.createPage();
+  var session = await page.createSession();
+
+  await session.evaluate(`
+    function createStyleSheet(textContent)
+    {
+        var styleElement = document.createElement('style');
+        styleElement.textContent = textContent;
+        document.head.appendChild(styleElement);
+        return styleElement;
+    }
+
+    window.styleElement1 = createStyleSheet('body.class1 { color: red; } \\n /*# sourceURL=foo.css */');
+    window.styleElement2 = createStyleSheet('body.class2 { color: green; } \\n /*# sourceURL=bar.css */');
+  `);
+
+  InspectorTest.log('\nRunning test');
+  InspectorTest.log('Opening front-end for the first time');
+  await runTest(session);
+  InspectorTest.log('Closing inspector.');
+  InspectorTest.log('\nRemoving style sheet.\n');
+  session.evaluate('setTimeout(() => document.head.removeChild(styleElement1), 0)');
+  await session.disconnect();
+
+  InspectorTest.log('Reopening inspector.');
+  session = await page.createSession();
+  InspectorTest.log('Running test');
+  InspectorTest.log('Opening front-end second time');
+  await runTest(session);
+  InspectorTest.completeTest();
+})();
+
+async function runTest(session) {
+  var headersAdded = [];
+  session.Protocol.CSS.onStyleSheetAdded(response => headersAdded.push(response.params.header));
+
+  var headersRemoved = [];
+  session.Protocol.CSS.onStyleSheetRemoved(response => headersRemoved.push(response.params.styleSheetId));
+
+  InspectorTest.log('Enabling CSS domain.');
+  session.Protocol.DOM.enable();
+  await session.Protocol.CSS.enable();
+
+  var headers = {};
+  headersAdded.sort((a, b) => a.styleSheetId - b.styleSheetId);
+  for (var header of headersAdded) {
+    headers[header.styleSheetId] = header.sourceURL;
+    InspectorTest.log(' - style sheet added: ' + header.sourceURL);
+  }
+
+  headersRemoved.sort();
+  for (var styleSheetId of headersRemoved)
+    InspectorTest.log(' - style sheet removed: ' + headers[styleSheetId]);
+}