Create a new local context class.

third_party/WebKit/Source/core/css/parser/CSSParserLocalContext.cpp

Index: third_party/WebKit/Source/core/css/parser/CSSParserLocalContext.cpp
diff --git a/third_party/WebKit/Source/core/css/parser/CSSParserLocalContext.cpp b/third_party/WebKit/Source/core/css/parser/CSSParserLocalContext.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..c2f8ffccdb505f33bf33b8871be6848f87927162
--- /dev/null
+++ b/third_party/WebKit/Source/core/css/parser/CSSParserLocalContext.cpp
@@ -0,0 +1,18 @@
+// 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.
+
+#include "core/css/parser/CSSParserLocalContext.h"
+
+namespace blink {
+
+CSSParserLocalContext::CSSParserLocalContext() : use_alias_parsing_(false) {}
+
+CSSParserLocalContext::CSSParserLocalContext(bool use_alias_parsing)
+    : use_alias_parsing_(use_alias_parsing) {}
+
+bool CSSParserLocalContext::GetUseAliasParsing() {
+  return use_alias_parsing_;
+}
+
+}  // namespace blink