mash: Migrate ScopedTargetRootWindow to //ash/common

ash/common/wm_shell.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_WM_SHELL_H_
 #define ASH_COMMON_WM_SHELL_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 93 matching lines @@
   }
 
   MruWindowTracker* mru_window_tracker() { return mru_window_tracker_.get(); }
 
   MediaDelegate* media_delegate() { return media_delegate_.get(); }
 
   NewWindowDelegate* new_window_delegate() {
     return new_window_delegate_.get();
   }
 
+  // NOTE: Prefer ScopedRootWindowForNewWindows when setting temporarily.
+  void set_root_window_for_new_windows(WmWindow* root) {
+    root_window_for_new_windows_ = root;
+  }
+
   ShelfDelegate* shelf_delegate() { return shelf_delegate_.get(); }
 
   ShelfModel* shelf_model() { return shelf_model_.get(); }
 
   SystemTrayNotifier* system_tray_notifier() {
     return system_tray_notifier_.get();
   }
 
   SystemTrayDelegate* system_tray_delegate() {
     return system_tray_delegate_.get();
@@ skipping 15 matching lines @@
 
   virtual WmWindow* GetFocusedWindow() = 0;
   virtual WmWindow* GetActiveWindow() = 0;
 
   virtual WmWindow* GetPrimaryRootWindow() = 0;
 
   // Returns the root window for the specified display.
   virtual WmWindow* GetRootWindowForDisplayId(int64_t display_id) = 0;
 
   // Returns the root window that newly created windows should be added to.
+  // Value can be temporarily overridden using ScopedRootWindowForNewWindows.
   // NOTE: this returns the root, newly created window should be added to the
   // appropriate container in the returned window.
-  virtual WmWindow* GetRootWindowForNewWindows() = 0;
+  WmWindow* GetRootWindowForNewWindows();
 
   // Retuns the display info associated with |display_id|.
   // TODO(msw): Remove this when DisplayManager has been moved. crbug.com/622480
   virtual const DisplayInfo& GetDisplayInfo(int64_t display_id) const = 0;
 
   // Matches that of DisplayManager::IsActiveDisplayId().
   // TODO: Remove this when DisplayManager has been moved. crbug.com/622480
   virtual bool IsActiveDisplayId(int64_t display_id) const = 0;
 
   // Returns true if the first window shown on first run should be
@@ skipping 152 matching lines @@
   void CreateMruWindowTracker();
   void DeleteMruWindowTracker();
 
   void DeleteToastManager();
 
   void SetAcceleratorController(
       std::unique_ptr<AcceleratorController> accelerator_controller);
 
  private:
   friend class AcceleratorControllerTest;
+  friend class ScopedRootWindowForNewWindows;
   friend class Shell;
 
   static WmShell* instance_;
 
   base::ObserverList<ShellObserver> shell_observers_;
   std::unique_ptr<ShellDelegate> delegate_;
 
   std::unique_ptr<AcceleratorController> accelerator_controller_;
   std::unique_ptr<AccessibilityDelegate> accessibility_delegate_;
   std::unique_ptr<BrightnessControlDelegate> brightness_control_delegate_;
   std::unique_ptr<FocusCycler> focus_cycler_;
   std::unique_ptr<KeyboardBrightnessControlDelegate>
       keyboard_brightness_control_delegate_;
   std::unique_ptr<KeyboardUI> keyboard_ui_;
   std::unique_ptr<MaximizeModeController> maximize_mode_controller_;
   std::unique_ptr<MediaDelegate> media_delegate_;
   std::unique_ptr<MruWindowTracker> mru_window_tracker_;
   std::unique_ptr<NewWindowDelegate> new_window_delegate_;
   std::unique_ptr<ShelfDelegate> shelf_delegate_;
   std::unique_ptr<ShelfModel> shelf_model_;
   std::unique_ptr<SystemTrayNotifier> system_tray_notifier_;
   std::unique_ptr<SystemTrayDelegate> system_tray_delegate_;
   std::unique_ptr<ToastManager> toast_manager_;
   std::unique_ptr<WindowCycleController> window_cycle_controller_;
   std::unique_ptr<WindowSelectorController> window_selector_controller_;
 
   base::ObserverList<LockStateObserver> lock_state_observers_;
 
+  // See comment for GetRootWindowForNewWindows().
+  WmWindow* root_window_for_new_windows_ = nullptr;
+  WmWindow* scoped_root_window_for_new_windows_ = nullptr;
+
   bool simulate_modal_window_open_for_testing_ = false;
 
 #if defined(OS_CHROMEOS)
   std::unique_ptr<LogoutConfirmationController> logout_confirmation_controller_;
 #endif
 };
 
 }  // namespace ash
 
 #endif  // ASH_COMMON_WM_SHELL_H_