Break dependency between ash::DisplayManager and ash::ScreenAsh

ash/display/display_manager.h

 // Copyright (c) 2012 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_DISPLAY_DISPLAY_MANAGER_H_
 #define ASH_DISPLAY_DISPLAY_MANAGER_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <memory>
 #include <string>
 #include <vector>
 
 #include "ash/ash_export.h"
 #include "base/compiler_specific.h"
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
+#include "base/observer_list.h"
 #include "ui/display/display.h"
+#include "ui/display/display_observer.h"
 #include "ui/display/manager/display_layout.h"
 #include "ui/display/manager/managed_display_info.h"
 
 #if defined(OS_CHROMEOS)
 #include "ui/display/chromeos/display_configurator.h"
 #endif
 
 namespace aura {
 class Window;
 }
 
 namespace chromeos {
 class DisplayNotificationsTest;
 }
 
 namespace display {
 class DisplayLayoutStore;
+class DisplayObserver;
+class Screen;
 }
 
 namespace gfx {
 class Insets;
 class Rect;
 }
 
 namespace ash {
 class AcceleratorControllerTest;
-class ScreenAsh;
 
 using DisplayInfoList = std::vector<display::ManagedDisplayInfo>;
 
 namespace test {
 class AshTestBase;
 class DisplayManagerTestApi;
 class SystemGestureEventFilterTest;
 }
 
 // DisplayManager maintains the current display configurations,
@@ skipping 31 matching lines @@
   // 3) UNIFIED mode creates single desktop across multiple displays.
   enum MultiDisplayMode {
     EXTENDED = 0,
     MIRRORING,
     UNIFIED,
   };
 
   // The display ID for a virtual display assigned to a unified desktop.
   static int64_t kUnifiedDisplayId;
 
-  DisplayManager();
+  explicit DisplayManager(std::unique_ptr<display::Screen> screen);
 #if defined(OS_CHROMEOS)
   ~DisplayManager() override;
 #else
   virtual ~DisplayManager();
 #endif
 
   display::DisplayLayoutStore* layout_store() { return layout_store_.get(); }
 
   void set_delegate(Delegate* delegate) { delegate_ = delegate; }
 
@@ skipping 209 matching lines @@
   // impl to |SetDefaultMultiDisplayMode|.
   void ReconfigureDisplays();
 
   // Update the bounds of the display given by |display_id|.
   bool UpdateDisplayBounds(int64_t display_id, const gfx::Rect& new_bounds);
 
   // Creates mirror window asynchronously if the software mirror mode
   // is enabled.
   void CreateMirrorWindowAsyncIfAny();
 
-  // Create a screen instance to be used during shutdown.
-  void CreateScreenForShutdown() const;
-
   // A unit test may change the internal display id (which never happens on
   // a real device). This will update the mode list for internal display
   // for this test scenario.
   void UpdateInternalManagedDisplayModeListForTest();
 
   // Zoom the internal display.
   bool ZoomInternalDisplay(bool up);
 
   // Reset the internal display zoom.
   void ResetInternalDisplayZoom();
 
+  // Notifies observers of display configuration changes.
+  void NotifyMetricsChanged(const display::Display& display, uint32_t metrics);
+  void NotifyDisplayAdded(const display::Display& display);
+  void NotifyDisplayRemoved(const display::Display& display);
+
+  // Delegated from the Screen implementation.
+  void AddObserver(display::DisplayObserver* observer);
+  void RemoveObserver(display::DisplayObserver* observer);
+
  private:
   FRIEND_TEST_ALL_PREFIXES(ExtendedDesktopTest, ConvertPoint);
   FRIEND_TEST_ALL_PREFIXES(DisplayManagerTest, TestNativeDisplaysChanged);
   FRIEND_TEST_ALL_PREFIXES(DisplayManagerTest,
                            NativeDisplaysChangedAfterPrimaryChange);
   FRIEND_TEST_ALL_PREFIXES(DisplayManagerTest, AutomaticOverscanInsets);
   FRIEND_TEST_ALL_PREFIXES(DisplayManagerTest, Rotate);
   friend class AcceleratorControllerTest;
   friend class DisplayManagerTest;
   friend class chromeos::DisplayNotificationsTest;
@@ skipping 60 matching lines @@
   void RunPendingTasksForTest();
 
   // Applies the |layout| and updates the bounds of displays in |display_list|.
   // |updated_ids| contains the ids for displays whose bounds have changed.
   void ApplyDisplayLayout(const display::DisplayLayout& layout,
                           display::DisplayList* display_list,
                           std::vector<int64_t>* updated_ids);
 
   Delegate* delegate_;  // not owned.
 
-  std::unique_ptr<ScreenAsh> screen_;
+  std::unique_ptr<display::Screen> screen_;
 
   std::unique_ptr<display::DisplayLayoutStore> layout_store_;
 
   int64_t first_display_id_;
 
   // List of current active displays.
   display::DisplayList active_display_list_;
   // This list does not include the displays that will be removed if
   // |UpdateDisplaysWith| is under execution.
   // See https://crbug.com/632755
@@ skipping 28 matching lines @@
   display::DisplayList software_mirroring_display_list_;
 
   // User preference for rotation lock of the internal display.
   bool registered_internal_display_rotation_lock_;
 
   // User preference for the rotation of the internal display.
   display::Display::Rotation registered_internal_display_rotation_;
 
   bool unified_desktop_enabled_;
 
+  base::ObserverList<display::DisplayObserver> observers_;
+
   base::WeakPtrFactory<DisplayManager> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(DisplayManager);
 };
 
 }  // namespace ash
 
 #endif  // ASH_DISPLAY_DISPLAY_MANAGER_H_