Revert [MacViews] Implemented text context menu

ui/gfx/decorated_text_mac.h

Index: ui/gfx/decorated_text_mac.h
diff --git a/ui/gfx/decorated_text_mac.h b/ui/gfx/decorated_text_mac.h
deleted file mode 100644
index 78d985d6597d0e70940bf041b6ee9ceaafef2368..0000000000000000000000000000000000000000
--- a/ui/gfx/decorated_text_mac.h
+++ /dev/null
@@ -1,22 +0,0 @@
-// Copyright 2017 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_GFX_DECORATED_TEXT_MAC_H_
-#define UI_GFX_DECORATED_TEXT_MAC_H_
-
-#include "ui/gfx/gfx_export.h"
-
-@class NSAttributedString;
-
-namespace gfx {
-
-struct DecoratedText;
-
-// Returns a NSAttributedString from |decorated_text|.
-GFX_EXPORT NSAttributedString* GetAttributedStringFromDecoratedText(
-    const DecoratedText& decorated_text);
-
-}  // namespace gfx
-
-#endif  // UI_GFX_DECORATED_TEXT_MAC_H_