Move DisplayList to display; add ScreenBase.

ui/views/mus/display_list.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 UI_VIEWS_MUS_DISPLAY_LIST_H_
-#define UI_VIEWS_MUS_DISPLAY_LIST_H_
-
-#include <stdint.h>
-
-#include <vector>
-
-#include "base/observer_list.h"
-#include "mojo/public/cpp/bindings/binding.h"
-#include "ui/display/display.h"
-#include "ui/views/mus/mus_export.h"
-
-namespace display {
-class Display;
-class DisplayObserver;
-}
-
-namespace views {
-
-// Maintains an ordered list of display::Displays as well as operations to add,
-// remove and update said list. Additionally maintains display::DisplayObservers
-// and updates them as appropriate.
-class VIEWS_MUS_EXPORT DisplayList {
- public:
-  using Displays = std::vector<display::Display>;
-
-  enum class Type {
-    PRIMARY,
-    NOT_PRIMARY,
-  };
-
-  DisplayList();
-  ~DisplayList();
-
-  void AddObserver(display::DisplayObserver* observer);
-  void RemoveObserver(display::DisplayObserver* observer);
-
-  const Displays& displays() const { return displays_; }
-
-  Displays::const_iterator FindDisplayById(int64_t id) const;
-  Displays::iterator FindDisplayById(int64_t id);
-
-  Displays::const_iterator GetPrimaryDisplayIterator() const;
-
-  // Updates the cached id based on display.id() as well as whether the Display
-  // is the primary display.
-  void UpdateDisplay(const display::Display& display, Type type);
-
-  // Adds a new Display.
-  void AddDisplay(const display::Display& display, Type type);
-
-  // Removes the Display with the specified id.
-  void RemoveDisplay(int64_t id);
-
- private:
-  std::vector<display::Display> displays_;
-  int primary_display_index_ = -1;
-  base::ObserverList<display::DisplayObserver> observers_;
-
-  DISALLOW_COPY_AND_ASSIGN(DisplayList);
-};
-
-}  // namespace views
-
-#endif  // UI_VIEWS_MUS_DISPLAY_LIST_H_