Remove "solo window" feature

ash/wm/solo_window_tracker.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_SOLO_WINDOW_TRACKER_H_
-#define ASH_WM_SOLO_WINDOW_TRACKER_H_
-
-#include <vector>
-
-#include "ash/ash_export.h"
-#include "ash/wm/dock/docked_window_layout_manager_observer.h"
-#include "base/compiler_specific.h"
-#include "base/memory/scoped_ptr.h"
-#include "ui/aura/window_observer.h"
-#include "ui/gfx/rect.h"
-
-namespace aura {
-class RootWindow;
-class Window;
-}
-
-namespace ash {
-
-// Class which keeps track of the window (if any) which should use the solo
-// window header. The solo window header is very transparent and is used when
-// there is only one visible window and the window is not maximized or
-// fullscreen. The solo window header is not used for either panels or docked
-// windows.
-class ASH_EXPORT SoloWindowTracker
-    : public aura::WindowObserver,
-      public internal::DockedWindowLayoutManagerObserver {
- public:
-  explicit SoloWindowTracker(aura::RootWindow* root_window);
-  virtual ~SoloWindowTracker();
-
-  // Enable/Disable solo headers.
-  static void SetSoloHeaderEnabled(bool enabled);
-
-  // Returns the window, if any, which should use the solo window header.
-  aura::Window* GetWindowWithSoloHeader();
-
- private:
-  // Updates the window which would use the solo header if the window were not
-  // maximized or fullscreen. If |ignore_window| is not NULL, it is ignored for
-  // counting valid candidates. This is useful when there is a window which is
-  // about to be moved to a different root window or about to be closed.
-  void UpdateSoloWindow(aura::Window* ignore_window);
-
-  // Returns true if there is a visible docked window.
-  bool AnyVisibleWindowDocked() const;
-
-  // aura::WindowObserver overrides:
-  virtual void OnWindowAdded(aura::Window* new_window) OVERRIDE;
-  virtual void OnWillRemoveWindow(aura::Window* window) OVERRIDE;
-  virtual void OnWindowVisibilityChanged(aura::Window* window,
-                                         bool visible) OVERRIDE;
-
-  // ash::internal::DockedWindowLayoutManagerObserver override:
-  virtual void OnDockBoundsChanging(const gfx::Rect& new_bounds,
-                                    Reason reason) OVERRIDE;
-
-  // The containers whose children can use the solo header.
-  std::vector<aura::Window*> containers_;
-
-  // The dock's bounds.
-  gfx::Rect dock_bounds_;
-
-  // The window which would use the solo header if it were not maximized or
-  // fullscreen.
-  aura::Window* solo_window_;
-
-  // Class which observes changes in |solo_window_|'s show type.
-  class SoloWindowObserver;
-  scoped_ptr<SoloWindowObserver> solo_window_observer_;
-
-  DISALLOW_COPY_AND_ASSIGN(SoloWindowTracker);
-};
-
-}  // namespace ash
-
-#endif // ASH_WM_SOLO_WINDOW_TRACKER_H_