Remove "solo window" feature

ash/root_window_controller.cc

 // Copyright (c) 2012 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.
 
 #include "ash/root_window_controller.h"
 
 #include <queue>
 #include <vector>
 
 #include "ash/ash_constants.h"
@@ skipping 18 matching lines @@
 #include "ash/touch/touch_hud_debug.h"
 #include "ash/touch/touch_hud_projection.h"
 #include "ash/touch/touch_observer_hud.h"
 #include "ash/wm/always_on_top_controller.h"
 #include "ash/wm/base_layout_manager.h"
 #include "ash/wm/dock/docked_window_layout_manager.h"
 #include "ash/wm/panels/panel_layout_manager.h"
 #include "ash/wm/panels/panel_window_event_handler.h"
 #include "ash/wm/root_window_layout_manager.h"
 #include "ash/wm/screen_dimmer.h"
-#include "ash/wm/solo_window_tracker.h"
 #include "ash/wm/stacking_controller.h"
 #include "ash/wm/status_area_layout_manager.h"
 #include "ash/wm/system_background_controller.h"
 #include "ash/wm/system_modal_container_layout_manager.h"
 #include "ash/wm/toplevel_window_event_handler.h"
 #include "ash/wm/window_properties.h"
 #include "ash/wm/window_state.h"
 #include "ash/wm/window_util.h"
 #include "ash/wm/workspace_controller.h"
 #include "base/command_line.h"
@@ skipping 395 matching lines @@
     // before move it to |kDesktopController|.
     DCHECK_EQ(controller->widget(), widget);
     // Release the old controller and close its background widget.
     SetWallpaperController(controller);
   }
 }
 
 void RootWindowController::CloseChildWindows() {
   mouse_event_target_.reset();
 
-  // |solo_window_tracker_| must be shut down before windows are destroyed.
-  if (solo_window_tracker_) {
-    if (docked_layout_manager_)
-      docked_layout_manager_->RemoveObserver(solo_window_tracker_.get());
-    solo_window_tracker_.reset();
-  }
-
   // Deactivate keyboard container before closing child windows and shutting
   // down associated layout managers.
   DeactivateKeyboard(Shell::GetInstance()->keyboard_controller());
 
   // panel_layout_manager_ needs to be shut down before windows are destroyed.
   if (panel_layout_manager_) {
     panel_layout_manager_->Shutdown();
     panel_layout_manager_ = NULL;
   }
   // docked_layout_manager_ needs to be shut down before windows are destroyed.
@@ skipping 215 matching lines @@
     root_window_layout()->OnWindowResized();
     shell->desktop_background_controller()->OnRootWindowAdded(root_window());
     shell->high_contrast_controller()->OnRootWindowAdded(
         root_window_->window());
     root_window_->host()->Show();
 
     // Create a shelf if a user is already logged in.
     if (shell->session_state_delegate()->NumberOfLoggedInUsers())
       shelf()->CreateShelf();
   }
-
-  solo_window_tracker_.reset(new SoloWindowTracker(root_window_.get()));
-  if (docked_layout_manager_)
-    docked_layout_manager_->AddObserver(solo_window_tracker_.get());
 }
 
 void RootWindowController::InitLayoutManagers() {
   root_window_layout_ = new RootWindowLayoutManager(root_window());
   root_window()->SetLayoutManager(root_window_layout_);
 
   aura::Window* default_container =
       GetContainer(kShellWindowId_DefaultContainer);
   // Workspace manager has its own layout managers.
   workspace_controller_.reset(
@@ skipping 281 matching lines @@
     DisableTouchHudProjection();
 }
 
 RootWindowController* GetRootWindowController(
     const aura::Window* root_window) {
   return root_window ? GetRootWindowSettings(root_window)->controller : NULL;
 }
 
 }  // namespace internal
 }  // namespace ash