Add parser support for generators.

src/scanner.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 35 matching lines @@
 // parsers to signify their (initial) mode of operation.
 enum ParsingFlags {
   kNoParsingFlags = 0,
   // Embed LanguageMode values in parsing flags, i.e., equivalent to:
   // CLASSIC_MODE = 0,
   // STRICT_MODE,
   // EXTENDED_MODE,
   kLanguageModeMask = 0x03,
   kAllowLazy = 0x04,
   kAllowNativesSyntax = 0x08,
-  kAllowModules = 0x10
+  kAllowModules = 0x10,
+  kAllowGenerators = 0x20
 };
 
 STATIC_ASSERT((kLanguageModeMask & CLASSIC_MODE) == CLASSIC_MODE);
 STATIC_ASSERT((kLanguageModeMask & STRICT_MODE) == STRICT_MODE);
 STATIC_ASSERT((kLanguageModeMask & EXTENDED_MODE) == EXTENDED_MODE);
 
 
 // Returns the value (0 .. 15) of a hexadecimal character c.
 // If c is not a legal hexadecimal character, returns a value < 0.
 inline int HexValue(uc32 c) {
@@ skipping 494 matching lines @@
   bool has_multiline_comment_before_next_;
   // Whether we scan 'let' as a keyword for harmony block-scoped let bindings.
   bool harmony_scoping_;
   // Whether we scan 'module', 'import', 'export' as keywords.
   bool harmony_modules_;
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_SCANNER_H_