chromeos: Move files in //ash/common to //ash, part 2

ash/wm_activation_observer.h

Index: ash/wm_activation_observer.h
diff --git a/ash/common/wm_activation_observer.h b/ash/wm_activation_observer.h
similarity index 86%
rename from ash/common/wm_activation_observer.h
rename to ash/wm_activation_observer.h
index b2b9a6ddb2eb517424f0028ef4ce6268443f5ce5..49f8499c96df1d55e85d405ad505f053eed41f3e 100644
--- a/ash/common/wm_activation_observer.h
+++ b/ash/wm_activation_observer.h
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef ASH_COMMON_WM_ACTIVATION_OBSERVER_H_
-#define ASH_COMMON_WM_ACTIVATION_OBSERVER_H_
+#ifndef ASH_WM_ACTIVATION_OBSERVER_H_
+#define ASH_WM_ACTIVATION_OBSERVER_H_
 
 #include "ash/ash_export.h"
 
@@ -29,4 +29,4 @@ class ASH_EXPORT WmActivationObserver {
 
 }  // namespace ash
 
-#endif  // ASH_COMMON_WM_ACTIVATION_OBSERVER_H_
+#endif  // ASH_WM_ACTIVATION_OBSERVER_H_