[DevTools] New harness for inspector-protocol layout tests

third_party/WebKit/LayoutTests/inspector-protocol/accessibility/accessibility-nameSources-buttons.js

+(async function(testRunner) {
+  let {page, session, dp} = await testRunner.startHTML(`
+     <style>
+     body.done .tests {
+       display: none;
+     }
+     </style>
+     <script>
+       function done() {
+           document.body.classList.add('done');
+       }
+     </script>
+     <!-- Compare with accessibility/name-calc-native-markup-buttons.html' -->
+     <div class='tests'>
+       <button id='button1'></button>
+
+       <button id='button2'>button2-content</button>
+
+       <button id='button3'><img src='resources/cake.png'></button>
+
+       <button id='button4'><img src='resources/cake.png' alt='cake'></button>
+
+       <button id='button5'>I love <img src='resources/cake.png'>!</button>
+
+       <button id='button6'>I love <img src='resources/cake.png' alt='cake'>!</button>
+
+       <button id='button7' title='button7-title'></button>
+
+       <button id='button8' title='button8-title'>button8-content</button>
+
+       <button id='button9' title='button9-title'><img src='resources/cake.png'></button>
+
+       <button id='button10' title='button10-title'><img src='resources/cake.png' alt='cake'></button>
+
+       <button id='button11'>button11-content</button>
+       <label for='button11'>label-for-button11</label>
+     </div>
+  `, '');
+
+  var dumpAccessibilityNodesBySelectorAndCompleteTest =
+      (await testRunner.loadScript('../resources/accessibility-dumpAccessibilityNodes.js'))(testRunner, session);
+
+  var msg = await dp.DOM.getDocument();
+  dumpAccessibilityNodesBySelectorAndCompleteTest('button', false, msg);
+})