Revert of Resurrect Aura Linux accessibility.

ui/accessibility/platform/atk_util_auralinux.h

Index: ui/accessibility/platform/atk_util_auralinux.h
diff --git a/ui/accessibility/platform/atk_util_auralinux.h b/ui/accessibility/platform/atk_util_auralinux.h
deleted file mode 100644
index 349c41a53de07af1061fbb44f598efdb221be2e4..0000000000000000000000000000000000000000
--- a/ui/accessibility/platform/atk_util_auralinux.h
+++ /dev/null
@@ -1,30 +0,0 @@
-// Copyright 2015 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef UI_ACCESSIBILITY_AX_UTIL_AURALINUX_H_
-#define UI_ACCESSIBILITY_AX_UTIL_AURALINUX_H_
-
-#include "base/memory/singleton.h"
-#include "ui/accessibility/ax_export.h"
-
-namespace ui {
-
-// This singleton class initializes ATK (accessibility toolkit) and
-// registers an implementation of the AtkUtil class, a global class that
-// every accessible application needs to register once.
-class AtkUtilAuraLinux {
- public:
-  // Get the single instance of this class.
-  static AtkUtilAuraLinux* GetInstance();
-
-  AtkUtilAuraLinux();
-  virtual ~AtkUtilAuraLinux();
-
- private:
-  friend struct DefaultSingletonTraits<AtkUtilAuraLinux>;
-};
-
-}  // namespace ui
-
-#endif  // UI_ACCESSIBILITY_AX_UTIL_AURALINUX_H_