chromeos: Move files in //ash/common to //ash, part 1

ash/system/accessibility_observer.h

Index: ash/system/accessibility_observer.h
diff --git a/ash/common/system/accessibility_observer.h b/ash/system/accessibility_observer.h
similarity index 76%
rename from ash/common/system/accessibility_observer.h
rename to ash/system/accessibility_observer.h
index 5de1ea2b3162ae45b05bcd949ae7866f848d46f1..fb6b937176c71c5f64c2a041b915ffa7468e8c32 100644
--- a/ash/common/system/accessibility_observer.h
+++ b/ash/system/accessibility_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_SYSTEM_ACCESSIBILITY_OBSERVER_H_
-#define ASH_COMMON_SYSTEM_ACCESSIBILITY_OBSERVER_H_
+#ifndef ASH_SYSTEM_ACCESSIBILITY_OBSERVER_H_
+#define ASH_SYSTEM_ACCESSIBILITY_OBSERVER_H_
 
 #include "ash/ash_export.h"
 #include "ash/common/accessibility_types.h"
@@ -21,4 +21,4 @@ class ASH_EXPORT AccessibilityObserver {
 
 }  // namespace ash
 
-#endif  // ASH_COMMON_SYSTEM_ACCESSIBILITY_OBSERVER_H_
+#endif  // ASH_SYSTEM_ACCESSIBILITY_OBSERVER_H_