Moves ash/wm/common back into ash

ash/wm/common/wm_layout_manager.h

Index: ash/wm/common/wm_layout_manager.h
diff --git a/ash/wm/common/wm_layout_manager.h b/ash/wm/common/wm_layout_manager.h
index 0e9b26e47f07c3e151d80b079d0e607132eadaf9..d8be091f5a964fe3ddade21eca95c1b301d45f41 100644
--- a/ash/wm/common/wm_layout_manager.h
+++ b/ash/wm/common/wm_layout_manager.h
@@ -5,7 +5,7 @@
 #ifndef ASH_WM_COMMON_WM_LAYOUT_MANAGER_H_
 #define ASH_WM_COMMON_WM_LAYOUT_MANAGER_H_
 
-#include "ash/wm/common/ash_wm_common_export.h"
+#include "ash/ash_export.h"
 
 namespace gfx {
 class Rect;
@@ -19,7 +19,7 @@ class WmWindow;
 // Used to position the child WmWindows of a WmWindow. WmLayoutManager is called
 // at key points in a WmWindows life cycle thats allow sthe WmLayoutManager to
 // position or change child WmWindows.
-class ASH_WM_COMMON_EXPORT WmLayoutManager {
+class ASH_EXPORT WmLayoutManager {
  public:
   virtual ~WmLayoutManager() {}