Add panels as a single group of windows per display for overview window cycling.

ash/wm/overview/window_selector_item.h

Index: ash/wm/overview/window_selector_item.h
diff --git a/ash/wm/overview/window_selector_item.h b/ash/wm/overview/window_selector_item.h
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+++ b/ash/wm/overview/window_selector_item.h
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+// 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_SELECTOR_ITEM_H_
+#define ASH_WM_OVERVIEW_WINDOW_SELECTOR_ITEM_H_
+
+#include "base/compiler_specific.h"
+#include "ui/gfx/rect.h"
+
+namespace aura {
+class RootWindow;
+class Window;
+}
+
+namespace ash {
+
+// This class represents an item in overview mode. An item can have one or more
+// windows, of which only one can be activated by keyboard (i.e. alt+tab) but
+// any can be selected with a pointer (touch or mouse).
+class WindowSelectorItem {
+ public:
+  WindowSelectorItem();
+  virtual ~WindowSelectorItem();
+
+  // Returns the root window on which this item is shown.
+  virtual const aura::RootWindow* GetRootWindow() const = 0;
+
+  // Returns the targeted window given the event |target| window.
+  // Returns NULL if no Window in this item was selected.
+  virtual aura::Window* TargetedWindow(const aura::Window* target) const = 0;
+
+  // Restores |window| on exiting window overview rather than returning it
+  // to its previous state.
+  virtual void RestoreWindowOnExit(aura::Window* window) = 0;
+
+  // Returns the |window| to activate on selecting of this item.
+  virtual aura::Window* SelectionWindow() const = 0;
+
+  // Removes |window| from this item. Check empty() after calling this to see
+  // if the entire item is now empty.
+  virtual void RemoveWindow(const aura::Window* window) = 0;
+
+  // Returns true if this item has no more selectable windows (i.e. after
+  // calling RemoveWindow for the last contained window).
+  virtual bool empty() const = 0;
+
+  // Sets the bounds of this window selector item to |target_bounds| in the
+  // |root_window| root window.
+  void SetBounds(aura::RootWindow* root_window,
+                 const gfx::Rect& target_bounds);
+
+  // Returns the current bounds of this selector item.
+  const gfx::Rect& bounds() { return bounds_; }
+
+ protected:
+  virtual void SetItemBounds(aura::RootWindow* root_window,
+                             const gfx::Rect& target_bounds) = 0;
+
+ private:
+  // The bounds this item is fit to.
+  gfx::Rect bounds_;
+
+  DISALLOW_COPY_AND_ASSIGN(WindowSelectorItem);
+};
+
+}  // namespace ash
+
+#endif  // ASH_WM_OVERVIEW_WINDOW_SELECTOR_ITEM_H_