exo: Initial support for multiple displays in ARC

components/exo/wm_helper_ash.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 COMPONENTS_EXO_WM_HELPER_ASH_H_
 #define COMPONENTS_EXO_WM_HELPER_ASH_H_
 
 #include "ash/common/shell_observer.h"
 #include "ash/common/system/accessibility_observer.h"
+#include "ash/display/window_tree_host_manager.h"
 #include "base/macros.h"
 #include "components/exo/wm_helper.h"
 #include "ui/aura/client/cursor_client_observer.h"
 #include "ui/aura/client/focus_change_observer.h"
 #include "ui/events/devices/input_device_event_observer.h"
 #include "ui/wm/public/activation_change_observer.h"
 
 namespace exo {
 
 // A helper class for accessing WindowManager related features.
 class WMHelperAsh : public WMHelper,
                     public aura::client::ActivationChangeObserver,
                     public aura::client::FocusChangeObserver,
                     public aura::client::CursorClientObserver,
                     public ash::AccessibilityObserver,
                     public ash::ShellObserver,
+                    public ash::WindowTreeHostManager::Observer,
                     public ui::InputDeviceEventObserver {
  public:
   WMHelperAsh();
   ~WMHelperAsh() override;
 
   // Overriden from WMHelper:
   const display::ManagedDisplayInfo GetDisplayInfo(
       int64_t display_id) const override;
   aura::Window* GetContainer(int container_id) override;
   aura::Window* GetActiveWindow() const override;
@@ skipping 24 matching lines @@
 
   // Overridden from ash::AccessibilityObserver:
   void OnAccessibilityModeChanged(
       ash::AccessibilityNotificationVisibility notify) override;
 
   // Overriden from ash::ShellObserver:
   void OnMaximizeModeStarted() override;
   void OnMaximizeModeEnding() override;
   void OnMaximizeModeEnded() override;
 
+  // Overriden from ash::WindowTreeHostManager::Observer:
+  void OnDisplayConfigurationChanged() override;
+
   // Overriden from ui::InputDeviceEventObserver:
   void OnKeyboardDeviceConfigurationChanged() override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(WMHelperAsh);
 };
 
 }  // namespace exo
 
 #endif  // COMPONENTS_EXO_WM_HELPER_H_