Revert of Add FontFaceDescriptors IDL dictionary

Source/core/css/FontFaceDescriptors.idl

Index: Source/core/css/FontFaceDescriptors.idl
diff --git a/Source/core/css/FontFaceDescriptors.idl b/Source/core/css/FontFaceDescriptors.idl
deleted file mode 100644
index 1ba9ef1cadccdd963d0415e3016bf1c4e12385c6..0000000000000000000000000000000000000000
--- a/Source/core/css/FontFaceDescriptors.idl
+++ /dev/null
@@ -1,14 +0,0 @@
-// Copyright 2014 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.
-
-[
-    GarbageCollected
-] dictionary FontFaceDescriptors {
-    DOMString style = "normal";
-    DOMString weight = "normal";
-    DOMString stretch = "normal";
-    DOMString unicodeRange = "U+0-10FFFF";
-    DOMString variant = "normal";
-    DOMString featureSettings = "normal";
-};