chromeos: makes WindowManager not delete shell when connection to mus is lost

ash/mus/window_manager.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 ASH_MUS_WINDOW_MANAGER_H_
 #define ASH_MUS_WINDOW_MANAGER_H_
 
 #include <stdint.h>
 
 #include <memory>
 #include <set>
 
 #include "ash/root_window_controller.h"
 #include "ash/shell_delegate.h"
+#include "base/callback_forward.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "services/ui/common/types.h"
 #include "services/ui/public/interfaces/display/display_controller.mojom.h"
 #include "services/ui/public/interfaces/window_manager.mojom.h"
 #include "ui/aura/mus/window_manager_delegate.h"
 #include "ui/aura/mus/window_tree_client_delegate.h"
 
 namespace base {
 class SequencedWorkerPool;
@@ skipping 42 matching lines @@
 class WindowManager : public aura::WindowManagerDelegate,
                       public aura::WindowTreeClientDelegate {
  public:
   WindowManager(service_manager::Connector* connector, Config config);
   ~WindowManager() override;
 
   void Init(std::unique_ptr<aura::WindowTreeClient> window_tree_client,
             const scoped_refptr<base::SequencedWorkerPool>& blocking_pool,
             std::unique_ptr<ash::ShellDelegate> shell_delegate = nullptr);
 
+  // Sets the callback that is run once the connection to mus is lost. If not
+  // set shutdown occurs when the connection is lost (the Shell is deleted).
+  void SetLostConnectionCallback(base::OnceClosure closure);
+
   // Blocks waiting for the initial set of displays.
   bool WaitForInitialDisplays();
 
   // Called during shutdown to delete all the RootWindowControllers.
   void DeleteAllRootWindowControllers();
 
   Config config() const { return config_; }
 
   ScreenMus* screen() { return screen_.get(); }
 
@@ skipping 103 matching lines @@
       const gfx::Insets& insets,
       const std::vector<gfx::Rect>& additional_client_areas) override;
   bool IsWindowActive(aura::Window* window) override;
   void OnWmDeactivateWindow(aura::Window* window) override;
 
   service_manager::Connector* connector_;
   display::mojom::DisplayControllerPtr display_controller_;
 
   const Config config_;
 
+  base::OnceClosure lost_connection_callback_;
+
   std::unique_ptr<::wm::WMState> wm_state_;
   std::unique_ptr<aura::PropertyConverter> property_converter_;
 
   std::unique_ptr<aura::WindowTreeClient> window_tree_client_;
 
   aura::WindowManagerClient* window_manager_client_ = nullptr;
 
   std::unique_ptr<views::PointerWatcherEventRouter>
       pointer_watcher_event_router_;
 
@@ skipping 21 matching lines @@
 
   std::unique_ptr<ui::InputDeviceClient> input_device_client_;
 
   DISALLOW_COPY_AND_ASSIGN(WindowManager);
 };
 
 }  // namespace mus
 }  // namespace ash
 
 #endif  // ASH_MUS_WINDOW_MANAGER_H_