Shuffles and renames ash/common/wm classes

ash/root_window_controller.h

Index: ash/root_window_controller.h
diff --git a/ash/root_window_controller.h b/ash/root_window_controller.h
index 2cb22d133a85850d78065614447b150baaa32d67..71e1ba69ffd0b0282656a313c2471be2d2a3aa88 100644
--- a/ash/root_window_controller.h
+++ b/ash/root_window_controller.h
@@ -67,6 +67,7 @@ class SystemModalContainerLayoutManager;
 class SystemTray;
 class TouchHudDebug;
 class TouchHudProjection;
+class WmWindow;
 class WorkspaceController;
 
 #if defined(OS_CHROMEOS)
@@ -74,10 +75,6 @@ class BootSplashScreen;
 class AshTouchExplorationManager;
 #endif
 
-namespace wm {
-class WmWindow;
-}
-
 // This class maintains the per root window state for ash. This class
 // owns the root window and other dependent objects that should be
 // deleted upon the deletion of the root window. This object is