chromeos: Move files in //ash/common to //ash, part 1

ash/common/system/chromeos/palette/common_palette_tool.h

-// Copyright 2016 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_SYSTEM_CHROMEOS_PALETTE_COMMON_PALETTE_TOOL_H_
-#define ASH_COMMON_SYSTEM_CHROMEOS_PALETTE_COMMON_PALETTE_TOOL_H_
-
-#include "ash/common/system/chromeos/palette/palette_tool.h"
-#include "ash/common/system/tray/view_click_listener.h"
-#include "base/strings/string16.h"
-#include "base/time/time.h"
-
-namespace gfx {
-struct VectorIcon;
-}
-
-namespace ash {
-
-class HoverHighlightView;
-
-// A PaletteTool implementation with a standard view support.
-class CommonPaletteTool : public PaletteTool, public ash::ViewClickListener {
- protected:
-  explicit CommonPaletteTool(Delegate* delegate);
-  ~CommonPaletteTool() override;
-
-  // PaletteTool:
-  void OnViewDestroyed() override;
-  void OnEnable() override;
-  void OnDisable() override;
-
-  // ViewClickListener:
-  void OnViewClicked(views::View* sender) override;
-
-  // Returns the icon used in the palette tray on the left-most edge of the
-  // tool.
-  virtual const gfx::VectorIcon& GetPaletteIcon() const = 0;
-
-  // Creates a default view implementation to be returned by CreateView.
-  views::View* CreateDefaultView(const base::string16& name);
-
- private:
-  HoverHighlightView* highlight_view_ = nullptr;
-
-  // start_time_ is initialized when the tool becomes active.
-  // Used for recording UMA metrics.
-  base::TimeTicks start_time_;
-
-  DISALLOW_COPY_AND_ASSIGN(CommonPaletteTool);
-};
-
-}  // namespace ash
-
-#endif  // ASH_COMMON_SYSTEM_CHROMEOS_PALETTE_COMMON_PALETTE_TOOL_H_