Implement handling of arrow functions in the parser

src/scanner.h

Index: src/scanner.h
diff --git a/src/scanner.h b/src/scanner.h
index d71b994850be336df0c74f6d4f24c0ac6d9b5ea9..d63e9709ada6389687514f0a7e8c0077262e4b93 100644
--- a/src/scanner.h
+++ b/src/scanner.h
@@ -458,6 +458,8 @@ class Scanner {
     return &source_mapping_url_;
   }
 
+  bool IdentifierIsFutureStrictReserved(const AstRawString* string) const;
+
  private:
   // The current and look-ahead token.
   struct TokenDesc {
@@ -647,6 +649,7 @@ class Scanner {
   bool harmony_numeric_literals_;
 };
 
+
 } }  // namespace v8::internal
 
 #endif  // V8_SCANNER_H_