Implement handling of arrow functions in the parser

src/scanner.h

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Features shared by parsing and pre-parsing scanners.
 
 #ifndef V8_SCANNER_H_
 #define V8_SCANNER_H_
 
 #include "src/allocation.h"
@@ skipping 440 matching lines @@
   bool ScanRegExpPattern(bool seen_equal);
   // Returns true if regexp flags are scanned (always since flags can
   // be empty).
   bool ScanRegExpFlags();
 
   const LiteralBuffer* source_url() const { return &source_url_; }
   const LiteralBuffer* source_mapping_url() const {
     return &source_mapping_url_;
   }
 
+  bool IdentifierIsFutureStrictReserved(const AstRawString* string) const;
+
  private:
   // The current and look-ahead token.
   struct TokenDesc {
     Token::Value token;
     Location location;
     LiteralBuffer* literal_chars;
   };
 
   static const int kCharacterLookaheadBufferSize = 1;
 
@@ skipping 172 matching lines @@
   bool harmony_scoping_;
   // Whether we scan 'module', 'import', 'export' as keywords.
   bool harmony_modules_;
   // Whether we scan 0o777 and 0b111 as numbers.
   bool harmony_numeric_literals_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_SCANNER_H_