Moves WorkspaceEventHandler to ash/common

ash/mus/move_event_handler.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_MOVE_EVENT_HANDLER_H_
 #define ASH_MUS_MOVE_EVENT_HANDLER_H_
 
 #include <memory>
 
 #include "ash/common/wm/wm_toplevel_window_event_handler.h"
 #include "base/macros.h"
 #include "ui/aura/window_observer.h"
 #include "ui/events/event_handler.h"
 
 namespace aura {
 class Window;
 }
 
 namespace ui {
 class CancelModeEvent;
 class Window;
 class WindowManagerClient;
 }
 
 namespace ash {
 namespace mus {
 
 class WmWindowMus;
+class WorkspaceEventHandlerMus;
 
 // EventHandler attached to windows that may be dragged and/or resized. This
 // forwards to WmToplevelWindowEventHandler to handle the actual drag/resize.
+//
+// TODO(sky): rename this class to better reflect that it handles redirecting
+// events in addition to drag.
 class MoveEventHandler : public ui::EventHandler, public aura::WindowObserver {
  public:
   MoveEventHandler(ui::Window* mus_window,
                    ui::WindowManagerClient* window_manager_client,
                    aura::Window* aura_window);
   ~MoveEventHandler() override;
 
   // Retrieves the MoveEventHandler for an existing WmWindow.
   static MoveEventHandler* GetForWindow(WmWindow* wm_window);
 
@@ skipping 10 matching lines @@
   // Returns whether we're in a drag.
   bool IsDragInProgress();
 
   // Reverts a manually started drag started with AttemptToStartDrag().
   void RevertDrag();
 
  private:
   // Removes observer and EventHandler installed on |root_window_|.
   void Detach();
 
+  // Returns the WorkspaceEventHandlerMus, or null if the window is not in a
+  // workspace.
+  WorkspaceEventHandlerMus* GetWorkspaceEventHandlerMus();
+
   // Overridden from ui::EventHandler:
   void OnMouseEvent(ui::MouseEvent* event) override;
   void OnGestureEvent(ui::GestureEvent* event) override;
   void OnCancelMode(ui::CancelModeEvent* event) override;
 
   // Overridden from aura::WindowObserver:
   void OnWindowDestroying(aura::Window* window) override;
 
   WmWindowMus* wm_window_;
   ui::WindowManagerClient* window_manager_client_;
   // The root window of the aura::Window supplied to the constructor.
   // MoveEventHandler is added as a pre-target handler (and observer) of this.
   aura::Window* root_window_;
   wm::WmToplevelWindowEventHandler toplevel_window_event_handler_;
 
   DISALLOW_COPY_AND_ASSIGN(MoveEventHandler);
 };
 
 }  // namespace mus
 }  // namespace ash
 
 #endif  // ASH_MUS_MOVE_EVENT_HANDLER_H_