Notify about major session changes events.

ash/shelf/shelf_layout_manager.h

 // 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.
 
 #ifndef ASH_SHELF_SHELF_LAYOUT_MANAGER_H_
 #define ASH_SHELF_SHELF_LAYOUT_MANAGER_H_
 
 #include <vector>
 
 #include "ash/ash_export.h"
+#include "ash/session_state_observer.h"
 #include "ash/shelf/background_animator.h"
 #include "ash/shelf/shelf.h"
 #include "ash/shelf/shelf_types.h"
 #include "ash/shell_observer.h"
 #include "ash/system/status_area_widget.h"
 #include "ash/wm/dock/docked_window_layout_manager_observer.h"
 #include "ash/wm/lock_state_observer.h"
 #include "ash/wm/workspace/workspace_types.h"
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
@@ skipping 32 matching lines @@
 // width of the status area. This allows the shelf to draw the background and
 // layout to the status area.
 // To respond to bounds changes in the status area StatusAreaLayoutManager works
 // closely with ShelfLayoutManager.
 class ASH_EXPORT ShelfLayoutManager :
     public aura::LayoutManager,
     public ash::ShellObserver,
     public aura::client::ActivationChangeObserver,
     public DockedWindowLayoutManagerObserver,
     public keyboard::KeyboardControllerObserver,
-    public LockStateObserver {
+    public LockStateObserver,
+    public SessionStateObserver {
  public:
 
   // We reserve a small area on the edge of the workspace area to ensure that
   // the resize handle at the edge of the window can be hit.
   static const int kWorkspaceAreaVisibleInset;
 
   // When autohidden we extend the touch hit target onto the screen so that the
   // user can drag the shelf out.
   static const int kWorkspaceAreaAutoHideInset;
 
@@ skipping 102 matching lines @@
   virtual void OnMaximizeModeStarted() OVERRIDE;
   virtual void OnMaximizeModeEnded() OVERRIDE;
 
   // Overriden from aura::client::ActivationChangeObserver:
   virtual void OnWindowActivated(aura::Window* gained_active,
                                  aura::Window* lost_active) OVERRIDE;
 
   // Overridden from ash::LockStateObserver:
   virtual void OnLockStateEvent(LockStateObserver::EventType event) OVERRIDE;
 
+  // Overridden from ash::SessionStateObserver:
+  virtual void SessionStateChanged(
+      SessionStateDelegate::SessionState state) OVERRIDE;
+
   // TODO(harrym|oshima): These templates will be moved to
   // new Shelf class.
   // A helper function that provides a shortcut for choosing
   // values specific to a shelf alignment.
   template<typename T>
   T SelectValueForShelfAlignment(T bottom, T left, T right, T top) const {
     switch (GetAlignment()) {
       case SHELF_ALIGNMENT_BOTTOM:
         return bottom;
       case SHELF_ALIGNMENT_LEFT:
@@ skipping 205 matching lines @@
 
   // The show hide animation duration override or 0 for default.
   int duration_override_in_ms_;
 
   DISALLOW_COPY_AND_ASSIGN(ShelfLayoutManager);
 };
 
 }  // namespace ash
 
 #endif  // ASH_SHELF_SHELF_LAYOUT_MANAGER_H_