Create a unified UIElement interface for Widget, View and Window.

ash/common/devtools/ui_element.cc

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "ash/common/devtools/ui_element.h"
+
+namespace ash {
+namespace devtools {
+
+UIElement::UIElement() {}
+
+UIElement::~UIElement() {}
+
+UIElement* UIElement::GetInstance() {
+  DCHECK(instance_);
+  return instance_;
+}
+
+UIElement::UIElement(int node_id) {
+  node_id_ = node_id;
+}
+
+// static
+UIElement* UIElement::ConvertNodeIdToUIElement(int node_id) {
+  return GetInstance()->node_id_to_ui_element[node_id];
+}
+
+int UIElement::GetNodeId() const {
+  return node_id_;
+}
+
+}  // namespace devtools
+}  // namespace ash