Make GetRootWindow() return a Window instead of a RootWindow.

ash/wm/overview/window_overview.h

 // Copyright 2013 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_WM_OVERVIEW_WINDOW_OVERVIEW_H_
 #define ASH_WM_OVERVIEW_WINDOW_OVERVIEW_H_
 
 #include "base/compiler_specific.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/scoped_vector.h"
 #include "base/time/time.h"
 #include "ui/aura/window_tracker.h"
 #include "ui/events/event_handler.h"
 #include "ui/gfx/rect.h"
 
 namespace aura {
-
 class Window;
-class RootWindow;
-
 namespace client {
 class CursorClient;
 }
-
 }  // namespace aura
 
 namespace ui {
 class LocatedEvent;
 }
 
 namespace views {
 class Widget;
 }
 
 namespace ash {
 
 class WindowSelector;
 class WindowSelectorItem;
 
 // The WindowOverview shows a grid of all of your windows and allows selecting
 // a window by clicking or tapping on it. It also displays a selection widget
 // used to indicate the current selection when alt-tabbing between windows.
 class WindowOverview : public ui::EventHandler {
  public:
   typedef ScopedVector<WindowSelectorItem> WindowSelectorItemList;
 
   // Enters an overview mode displaying |windows| and dispatches methods
   // on |window_selector| when a window is selected or selection is canceled.
   // If |single_root_window| is not NULL, all windows will be positioned on the
   // given root window.
   WindowOverview(WindowSelector* window_selector,
                  WindowSelectorItemList* windows,
-                 aura::RootWindow* single_root_window);
+                 aura::Window* single_root_window);
   virtual ~WindowOverview();
 
   // Sets the selected window to be the window in position |index|.
   void SetSelection(size_t index);
 
   // Dispatched when the list of windows has changed.
   void OnWindowsChanged();
 
   // Moves the overview to only |root_window|.
-  void MoveToSingleRootWindow(aura::RootWindow* root_window);
+  void MoveToSingleRootWindow(aura::Window* root_window);
 
   // ui::EventHandler:
   virtual void OnKeyEvent(ui::KeyEvent* event) OVERRIDE;
   virtual void OnMouseEvent(ui::MouseEvent* event) OVERRIDE;
   virtual void OnTouchEvent(ui::TouchEvent* event) OVERRIDE;
 
  private:
   // Returns the target of |event| or NULL if the event is not targeted at
   // any of the windows in the selector.
   aura::Window* GetEventTarget(ui::LocatedEvent* event);
 
   // Returns the top-level window selected by targeting |window| or NULL if
   // no overview window was found for |window|.
   aura::Window* GetTargetedWindow(aura::Window* window);
 
   // Hide and track all hidden windows not in overview.
   void HideAndTrackNonOverviewWindows();
 
   // Position all of the windows based on the current selection mode.
   void PositionWindows();
   // Position all of the windows from |root_window| on |root_window|.
-  void PositionWindowsFromRoot(aura::RootWindow* root_window);
+  void PositionWindowsFromRoot(aura::Window* root_window);
   // Position all of the |windows| to fit on the |root_window|.
-  void PositionWindowsOnRoot(aura::RootWindow* root_window,
+  void PositionWindowsOnRoot(aura::Window* root_window,
                              const std::vector<WindowSelectorItem*>& windows);
 
   // Creates the selection widget.
   void InitializeSelectionWidget();
 
   // Returns the bounds for the selection widget for the windows_ at |index|.
   gfx::Rect GetSelectionBounds(size_t index);
 
   // Weak pointer to the window selector which owns this class.
   WindowSelector* window_selector_;
 
   // A weak pointer to the collection of windows in the overview wrapped by a
   // helper class which restores their state and helps transform them to other
   // root windows.
   WindowSelectorItemList* windows_;
 
   // Widget indicating which window is currently selected.
   scoped_ptr<views::Widget> selection_widget_;
 
   // Index of the currently selected window. This is used to determine when the
   // selection changes rows and use a different animation.
   size_t selection_index_;
 
   // If NULL, each root window displays an overview of the windows in that
   // display. Otherwise, all windows are in a single overview on
   // |single_root_window_|.
-  aura::RootWindow* single_root_window_;
+  aura::Window* single_root_window_;
 
   // The time when overview was started.
   base::Time overview_start_time_;
 
   // The cursor client used to lock the current cursor during overview.
   aura::client::CursorClient* cursor_client_;
 
   // Tracks windows which were hidden because they were not part of the
   // overview.
   aura::WindowTracker hidden_windows_;
 
   DISALLOW_COPY_AND_ASSIGN(WindowOverview);
 };
 
 }  // namespace ash
 
 #endif  // ASH_WM_OVERVIEW_WINDOW_OVERVIEW_H_