[Devtools] DataGrid & ViewportDataGrid now should resetNode for children

third_party/WebKit/LayoutTests/http/tests/inspector-unit/datagrid-items-attached-to-dom.js

Index: third_party/WebKit/LayoutTests/http/tests/inspector-unit/datagrid-items-attached-to-dom.js
diff --git a/third_party/WebKit/LayoutTests/http/tests/inspector-unit/datagrid-items-attached-to-dom.js b/third_party/WebKit/LayoutTests/http/tests/inspector-unit/datagrid-items-attached-to-dom.js
new file mode 100644
index 0000000000000000000000000000000000000000..efdcc8dbf3f600c8b2d589c17fb7ccc65b2f22a7
--- /dev/null
+++ b/third_party/WebKit/LayoutTests/http/tests/inspector-unit/datagrid-items-attached-to-dom.js
@@ -0,0 +1,55 @@
+TestRunner.loadLazyModules(['data_grid']).then(test);
+function test() {
+  TestRunner.addResult("This tests viewport datagrid.");
+
+  var div = document.createElement("div");
+  UI.inspectorView.element.appendChild(div);
+
+  var columns = [{id: "id", title: "ID column", width: "250px"}];
+  var dataGrid = new DataGrid.DataGrid(columns);
+  div.appendChild(dataGrid.element);
+  dataGrid.element.style.height = '150px';
+
+  var rootNode = dataGrid.rootNode();
+  var nodes = [];
+
+  for (var i = 0; i < 15; i++) {
+    var node = new DataGrid.DataGridNode({id: "a" + i});
+    rootNode.appendChild(node);
+    nodes.push(node);
+  }
+
+  dumpVisibleNodes();
+
+  TestRunner.addResult("Testing removal of some nodes");
+  nodes[0].remove();
+  nodes[1].remove();
+  nodes[3].remove();
+  nodes[5].remove();
+
+  TestRunner.addResult("Should be missing node 0, 1, 3, 5 from dom:");
+  dumpVisibleNodes();
+
+  TestRunner.addResult("Testing adding of some nodes back");
+  rootNode.insertChild(nodes[0], 0);
+  rootNode.insertChild(nodes[1], 1);
+  rootNode.insertChild(nodes[3], 3);
+  rootNode.insertChild(nodes[5], 5);
+
+  TestRunner.addResult("Should have nodes 0, 1, 3, 5 back in dom and previously added nodes removed:");
+  dumpVisibleNodes();
+
+  TestRunner.completeTest();
+
+  function dumpVisibleNodes() {
+    TestRunner.addResult("Nodes attached to dom:");
+    for (var node of nodes) {
+      var element = node.existingElement();
+      if (!element)
+        continue;
+      if (div.contains(element))
+        TestRunner.addResult(node.data.id);
+    }
+    TestRunner.addResult("");
+  }
+}