Converts remaining usage of WmLayoutManager to aura::LayoutManager

ash/keyboard/keyboard_observer_register.h

Index: ash/keyboard/keyboard_observer_register.h
diff --git a/ash/keyboard/keyboard_observer_register.h b/ash/keyboard/keyboard_observer_register.h
index a95aae421f1c9f6ce177dbf633876442b2ce9f70..e34f2d10e844b72c2926dd10ae808edcf3085da0 100644
--- a/ash/keyboard/keyboard_observer_register.h
+++ b/ash/keyboard/keyboard_observer_register.h
@@ -7,6 +7,10 @@
 
 #include "base/scoped_observer.h"
 
+namespace aura {
+class Window;
+}
+
 namespace keyboard {
 class KeyboardController;
 class KeyboardControllerObserver;
@@ -14,8 +18,6 @@ class KeyboardControllerObserver;
 
 namespace ash {
 
-class WmWindow;
-
 // Helper function to start/stop observing KeyboardController.
 // |keyboard_root_window| is the root window where KeyboardController changes
 // states.  |observer_root_window| is the root window relevant to the
@@ -25,8 +27,8 @@ class WmWindow;
 // false.
 void UpdateKeyboardObserverFromStateChanged(
     bool keyboard_activated,
-    WmWindow* keyboard_root_window,
-    WmWindow* observer_root_window,
+    aura::Window* keyboard_root_window,
+    aura::Window* observer_root_window,
     ScopedObserver<keyboard::KeyboardController,
                    keyboard::KeyboardControllerObserver>* keyboard_observer);