Make native syntax an early error in the preparser.

src/preparser.h

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 92 matching lines @@
 };
 
 
 class PreParser {
  public:
   enum PreParseResult {
     kPreParseStackOverflow,
     kPreParseSuccess
   };
 
+  enum Flags {
+    kNoFlags = 0,
+    kAllowLazy = 1,
+    kAllowNativesSyntax = 2
+  };
+
   ~PreParser() {}
 
   // Pre-parse the program from the character stream; returns true on
   // success (even if parsing failed, the pre-parse data successfully
   // captured the syntax error), and false if a stack-overflow happened
   // during parsing.
   static PreParseResult PreParseProgram(i::JavaScriptScanner* scanner,
                                         i::ParserRecorder* log,
-                                        bool allow_lazy,
+                                        int flags,
                                         uintptr_t stack_limit) {
-    return PreParser(scanner, log, stack_limit, allow_lazy).PreParse();
+    bool allow_lazy = (flags & kAllowLazy) != 0;
+    bool allow_natives_syntax = (flags & kAllowNativesSyntax) != 0;
+    return PreParser(scanner, log, stack_limit,
+                     allow_lazy, allow_natives_syntax).PreParse();
   }
 
  private:
   // Used to detect duplicates in object literals. Each of the values
   // kGetterProperty, kSetterProperty and kValueProperty represents
   // a type of object literal property. When parsing a property, its
   // type value is stored in the DuplicateFinder for the property name.
   // Values are chosen so that having intersection bits means the there is
   // an incompatibility.
   // I.e., you can add a getter to a property that already has a setter, since
@@ skipping 296 matching lines @@
     int materialized_literal_count_;
     int expected_properties_;
     int with_nesting_count_;
     bool strict_;
   };
 
   // Private constructor only used in PreParseProgram.
   PreParser(i::JavaScriptScanner* scanner,
             i::ParserRecorder* log,
             uintptr_t stack_limit,
-            bool allow_lazy)
+            bool allow_lazy,
+            bool allow_natives_syntax)
       : scanner_(scanner),
         log_(log),
         scope_(NULL),
         stack_limit_(stack_limit),
         strict_mode_violation_location_(i::Scanner::Location::invalid()),
         strict_mode_violation_type_(NULL),
         stack_overflow_(false),
-        allow_lazy_(true),
+        allow_lazy_(allow_lazy),
+        allow_natives_syntax_(allow_natives_syntax),
         parenthesized_function_(false),
         harmony_scoping_(scanner->HarmonyScoping()) { }
 
   // Preparse the program. Only called in PreParseProgram after creating
   // the instance.
   PreParseResult PreParse() {
     Scope top_scope(&scope_, kTopLevelScope);
     bool ok = true;
     int start_position = scanner_->peek_location().beg_pos;
     ParseSourceElements(i::Token::EOS, &ok);
@@ skipping 141 matching lines @@
                                      bool* ok);
 
   i::JavaScriptScanner* scanner_;
   i::ParserRecorder* log_;
   Scope* scope_;
   uintptr_t stack_limit_;
   i::Scanner::Location strict_mode_violation_location_;
   const char* strict_mode_violation_type_;
   bool stack_overflow_;
   bool allow_lazy_;
+  bool allow_natives_syntax_;
   bool parenthesized_function_;
   bool harmony_scoping_;
 };
 } }  // v8::preparser
 
 #endif  // V8_PREPARSER_H