Implement ES6 unicode escapes.

src/parser.h

 // Copyright 2012 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.
 
 #ifndef V8_PARSER_H_
 #define V8_PARSER_H_
 
 #include "src/allocation.h"
 #include "src/ast.h"
 #include "src/compiler.h"  // For CachedDataMode
@@ skipping 222 matching lines @@
   // out parameters.
   bool ParseIntervalQuantifier(int* min_out, int* max_out);
 
   // Parses and returns a single escaped character.  The character
   // must not be 'b' or 'B' since they are usually handle specially.
   uc32 ParseClassCharacterEscape();
 
   // Checks whether the following is a length-digit hexadecimal number,
   // and sets the value if it is.
   bool ParseHexEscape(int length, uc32* value);
+  // Like ParseHexEscape, but the length of the number is unlimited; the value
+  // must be at most max_value.
+  bool ParseUnlimitedLengthHexEscape(int max_value, uc32* value);
+  bool ParseUnicodeEscape(uc32* value);
 
   uc32 ParseOctalLiteral();
 
   // Tries to parse the input as a back reference.  If successful it
   // stores the result in the output parameter and returns true.  If
   // it fails it will push back the characters read so the same characters
   // can be reparsed.
   bool ParseBackReferenceIndex(int* index_out);
 
   CharacterRange ParseClassAtom(uc16* char_class);
@@ skipping 669 matching lines @@
  private:
   static const int kLiteralTypeSlot = 0;
   static const int kElementsSlot = 1;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(CompileTimeValue);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_PARSER_H_