Revert of Remove remaining window states where window is shown with opacity 0.

ash/wm/panels/panel_layout_manager.h

Index: ash/wm/panels/panel_layout_manager.h
diff --git a/ash/wm/panels/panel_layout_manager.h b/ash/wm/panels/panel_layout_manager.h
index fc42af271aa3ca4e09b72ae5b56ab17c50f7365e..f0c093d48c2bb83377090c890b4f44060da7bf0f 100644
--- a/ash/wm/panels/panel_layout_manager.h
+++ b/ash/wm/panels/panel_layout_manager.h
@@ -18,7 +18,6 @@
 #include "base/memory/scoped_ptr.h"
 #include "base/memory/weak_ptr.h"
 #include "ui/aura/layout_manager.h"
-#include "ui/aura/window_observer.h"
 #include "ui/keyboard/keyboard_controller.h"
 #include "ui/keyboard/keyboard_controller_observer.h"
 #include "ui/wm/public/activation_change_observer.h"
@@ -54,12 +53,11 @@
     : public aura::LayoutManager,
       public ShelfIconObserver,
       public ShellObserver,
-      public aura::WindowObserver,
-      public wm::WindowStateObserver,
       public aura::client::ActivationChangeObserver,
       public keyboard::KeyboardControllerObserver,
       public DisplayController::Observer,
-      public ShelfLayoutManagerObserver {
+      public ShelfLayoutManagerObserver,
+      public wm::WindowStateObserver {
  public:
   explicit PanelLayoutManager(aura::Window* panel_container);
   virtual ~PanelLayoutManager();
@@ -93,11 +91,6 @@
 
   // Overridden from ShellObserver
   virtual void OnShelfAlignmentChanged(aura::Window* root_window) OVERRIDE;
-
-  // Overridden from aura::WindowObserver
-  virtual void OnWindowPropertyChanged(aura::Window* window,
-                                       const void* key,
-                                       intptr_t old) OVERRIDE;
 
   // Overridden from ash::wm::WindowStateObserver
   virtual void OnPostWindowStateTypeChange(
@@ -139,8 +132,8 @@
     PanelCalloutWidget* callout_widget;
 
     // True on new and restored panel windows until the panel has been
-    // positioned. The first time Relayout is called the panel will be shown,
-    // and slide into position and this will be set to false.
+    // positioned. The first time Relayout is called the panel will slide into
+    // position and this will be set to false.
     bool slide_in;
   };