DevTools: Use FocusRestorer in SoftContextMenu

third_party/WebKit/LayoutTests/http/tests/inspector-unit/soft-context-menu.js

+var menu = new UI.SoftContextMenu([{
+  type: 'item',
+  label: 'First',
+  enabled: true
+},
+{
+  type: 'subMenu',
+  label: 'Second',
+  enabled: true,
+  subItems: [
+    {type: 'subMenu', label: 'Child 1', enabled: true, subItems: [{type: 'item', label: 'Grandchild', id: 'Grandchild', enabled: true}]},
+    {type: 'item', label: 'Child 2', enabled: true},
+    {type: 'item', label: 'Child 3', enabled: true},
+    {type: 'item', label: 'Child 4', enabled: true}
+  ]
+},
+{
+  type: 'separator',
+},{
+  type: 'item',
+  label: 'Third',
+  enabled: true
+}], item => TestRunner.addResult('Item Selected: ' + item));
+
+var initialFocusedElement = UI.inspectorView.element.createChild('div');
+initialFocusedElement.textContent = 'Initial Focused Element';
+initialFocusedElement.tabIndex = -1;
+initialFocusedElement.focus();
+
+dumpContextMenu();
+menu.show(document, new AnchorBox(50, 50, 0, 0));
+dumpContextMenu();
+pressKey('ArrowDown');
+pressKey('ArrowDown');
+pressKey('ArrowDown');
+pressKey('ArrowUp');
+pressKey('ArrowUp');
+pressKey('ArrowUp');
+pressKey('ArrowDown');
+TestRunner.addResult('Enter Submenu');
+pressKey('ArrowRight');
+pressKey('ArrowDown');
+pressKey('ArrowDown');
+pressKey('ArrowDown');
+TestRunner.addResult('Leave Submenu ArrowLeft');
+pressKey('ArrowLeft');
+pressKey('ArrowRight');
+TestRunner.addResult('Leave Submenu Escape');
+pressKey('Escape');
+TestRunner.addResult('Enter Sub-Submenu');
+pressKey(' ');
+pressKey('Enter');
+pressKey('Enter');
+TestRunner.completeTest();
+
+function pressKey(key) {
+  var element = document.deepActiveElement();
+  if (!element)
+    return;
+  element.dispatchEvent(TestRunner.createKeyEvent(key));
+  if (key === ' ')
+    key = 'Space';
+  TestRunner.addResult(key);
+  dumpContextMenu();
+}
+
+function dumpContextMenu() {
+  if (initialFocusedElement.hasFocus()) {
+    TestRunner.addResult('Initial focused element has focus');
+    return;
+  }
+  var selection = '';
+  var subMenu = menu;
+  var activeElement = document.deepActiveElement();
+  do {
+    if (selection)
+      selection += ' -> ';
+    if (subMenu._contextMenuElement === activeElement)
+      selection += '[';
+    if (subMenu._highlightedMenuItemElement)
+      selection += subMenu._highlightedMenuItemElement.textContent.replace(/[^A-z0-9 ]/g, '');
+    else
+      selection += 'null'
+    if (subMenu._contextMenuElement === activeElement)
+      selection += ']';
+  }
+  while (subMenu = subMenu._subMenu)
+  TestRunner.addResult(selection);
+}