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

ash/common/devtools/ui_element_delegate.h

Index: ash/common/devtools/ui_element_delegate.h
diff --git a/ash/common/devtools/ui_element_delegate.h b/ash/common/devtools/ui_element_delegate.h
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index 0000000000000000000000000000000000000000..dae189106fef569bf7d33bc9ee1641675b95c2ad
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+++ b/ash/common/devtools/ui_element_delegate.h
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+// 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.
+
+#ifndef ASH_COMMON_DEVTOOLS_UI_ELEMENT_DELEGATE_H_
+#define ASH_COMMON_DEVTOOLS_UI_ELEMENT_DELEGATE_H_
+
+#include "ash/ash_export.h"
+#include "ash/common/devtools/ash_devtools_dom_agent.h"
+#include "ash/common/wm_window.h"
+#include "ui/aura/window_observer.h"
+#include "ui/views/view.h"
+#include "ui/views/widget/widget.h"
+
+namespace ash {
+namespace devtools {
+
+class ASH_EXPORT UIElementDelegate {
+ public:
+  // For WindowElement
+  void NotifyOnWindowHierarchyChanging(
+      const aura::WindowObserver::HierarchyChangeParams& params);
+  void NotifyOnWindowHierarchyChanged(
+      const aura::WindowObserver::HierarchyChangeParams& params);
+  void NotifyRemoveWindowTree(WmWindow* window, bool remove_observer);
+  void NotifyAddWindowTree(WmWindow* window);
+  void NotfiyOnWindowBoundsChanged(WmWindow* window);
+
+  // For ViewElement
+  void NotifyRemoveViewTree(views::View* view,
+                            views::View* parent,
+                            bool remove_observer);
+  void NotifyAddViewTree(views::View* view);
+  void NotifyOnViewBoundsChanged(views::View* view);
+
+  // For WidgetElement
+  void NotifyOnWidgetBoundsChanged(views::Widget* widget);
+
+  void SetDelegate(AshDevToolsDOMAgent* dom_agent) {
+    dom_agent_delegate = dom_agent;
+  };
+
+  AshDevToolsDOMAgent* DomAgentDelegate() { return dom_agent_delegate; }
+
+ private:
+  AshDevToolsDOMAgent* dom_agent_delegate;
+
+  DISALLOW_COPY_AND_ASSIGN(UIElementDelegate);
+};
+
+}  // namespace devtools
+}  // namespace ash
+
+#endif  // ASH_COMMON_DEVTOOLS_UI_ELEMENT_DELEGATE_H_