Update event states in Env when target window has been destroyed.

ui/aura/window_event_dispatcher.h

 // Copyright 2014 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_AURA_WINDOW_EVENT_DISPATCHER_H_
 #define UI_AURA_WINDOW_EVENT_DISPATCHER_H_
 
 #include <memory>
 #include <vector>
 
@@ skipping 41 matching lines @@
 //             event dispatch.
 class AURA_EXPORT WindowEventDispatcher : public ui::EventProcessor,
                                           public ui::GestureEventHelper,
                                           public client::CaptureDelegate,
                                           public WindowObserver,
                                           public EnvObserver {
  public:
   explicit WindowEventDispatcher(WindowTreeHost* host);
   ~WindowEventDispatcher() override;
 
+  EnvInputStateController* env_controller() { return env_controller_.get(); }
+
   Window* mouse_pressed_handler() { return mouse_pressed_handler_; }
   Window* mouse_moved_handler() { return mouse_moved_handler_; }
 
   // Overridden from ui::EventProcessor:
   ui::EventTargeter* GetDefaultEventTargeter() override;
 
   // Repost event for re-processing. Used when exiting context menus.
   // We support the ET_MOUSE_PRESSED, ET_TOUCH_PRESSED and ET_GESTURE_TAP_DOWN
   // event types (although the latter is currently a no-op).
   void RepostEvent(const ui::LocatedEvent* event);
@@ skipping 206 matching lines @@
 
   // Used to schedule DispatchHeldEvents() when |move_hold_count_| goes to 0.
   base::WeakPtrFactory<WindowEventDispatcher> held_event_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(WindowEventDispatcher);
 };
 
 }  // namespace aura
 
 #endif  // UI_AURA_WINDOW_EVENT_DISPATCHER_H_