Add VectorIconButton functionality to ImageButton.

ui/views/controls/button/vector_icon_button.h

-// Copyright 2015 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 UI_VIEWS_CONTROLS_BUTTON_VECTOR_ICON_BUTTON_H_
-#define UI_VIEWS_CONTROLS_BUTTON_VECTOR_ICON_BUTTON_H_
-
-#include "base/macros.h"
-#include "ui/views/controls/button/image_button.h"
-
-namespace gfx {
-struct VectorIcon;
-enum class VectorIconId;
-}
-
-namespace views {
-
-class VectorIconButtonDelegate;
-
-// A button that has an image and no text, with the image defined by a vector
-// icon identifier.
-class VIEWS_EXPORT VectorIconButton : public views::ImageButton {
- public:
-  explicit VectorIconButton(VectorIconButtonDelegate* delegate);
-  ~VectorIconButton() override;
-
-  // Sets the icon to display and provides a callback which should return the
-  // text color from which to derive this icon's color.
-  void SetIcon(const gfx::VectorIcon& icon);
-
-  // views::ImageButton:
-  void OnThemeChanged() override;
-  void OnNativeThemeChanged(const ui::NativeTheme* theme) override;
-
- private:
-  // Performs the work common to both SetIcon() variants.
-  void OnSetIcon();
-
-  // Called when something may have affected the button's images or colors.
-  void UpdateImagesAndColors();
-
-  VectorIconButtonDelegate* delegate_;
-  const gfx::VectorIcon* icon_;
-
-  DISALLOW_COPY_AND_ASSIGN(VectorIconButton);
-};
-
-}  // namespace views
-
-#endif  // UI_VIEWS_CONTROLS_BUTTON_VECTOR_ICON_BUTTON_H_