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

ash/common/devtools/widget_element.h

Index: ash/common/devtools/widget_element.h
diff --git a/ash/common/devtools/widget_element.h b/ash/common/devtools/widget_element.h
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index 0000000000000000000000000000000000000000..877382c5b76cac46b34f313eeac6956bd4c3a1f9
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+++ b/ash/common/devtools/widget_element.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_WIDGET_ELEMENT_H_
+#define ASH_COMMON_DEVTOOLS_WIDGET_ELEMENT_H_
+
+#include "ash/common/devtools/ui_element.h"
+#include "ui/gfx/geometry/rect.h"
+#include "ui/views/widget/widget.h"
+#include "ui/views/widget/widget_observer.h"
+#include "ui/views/widget/widget_removals_observer.h"
+
+namespace ash {
+namespace devtools {
+
+class WidgetElement : public views::WidgetObserver,
+                      public views::WidgetRemovalsObserver,
+                      public UIElement {
+ public:
+  WidgetElement(views::Widget* widget);
+
+  // views::WidgetRemovalsObserver:
+  void OnWillRemoveView(views::Widget* widget, views::View* view) override;
+
+  // views::WidgetObserver:
+  void OnWidgetBoundsChanged(views::Widget* widget,
+                             const gfx::Rect& new_bounds) override;
+
+  bool GetBounds(gfx::Rect* bounds) override;
+  bool SetBounds(const gfx::Rect& bounds) override;
+  bool GetVisible(bool* visible) override;
+  bool SetVisible(bool visible) override;
+
+ private:
+  views::Widget* widget_;
+
+  DISALLOW_COPY_AND_ASSIGN(WidgetElement);
+};
+
+}  // namespace devtools
+}  // namespace ash
+
+#endif  // ASH_COMMON_DEVTOOLS_WIDGET_ELEMENT_H_