Add Array.prototype.reduce and .reduceRight.

src/messages.js

 // Copyright 2006-2008 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 80 matching lines @@
   illegal_eval:                 "Unsupported indirect eval() call",
   with_expression:              "%0 has no properties",
   illegal_invocation:           "Illegal invocation",
   no_setter_in_callback:        "Cannot set property %0 of %1 which has only a getter",
   apply_non_function:           "Function.prototype.apply was called on %0, which is a %1 and not a function",
   apply_wrong_args:             "Function.prototype.apply: Arguments list has wrong type",
   invalid_in_operator_use:      "Cannot use 'in' operator to search for '%0' in %1",
   instanceof_function_expected: "Expecting a function in instanceof check, but got %0",
   instanceof_nonobject_proto:   "Function has non-object prototype '%0' in instanceof check",
   null_to_object:               "Cannot convert null to object",
+  reduce_no_initial:            "Reduce of empty array with no initial value",
   // RangeError
   invalid_array_length:         "Invalid array length",
   invalid_array_apply_length:   "Function.prototype.apply supports only up to 1024 arguments",
   stack_overflow:               "Maximum call stack size exceeded",
   apply_overflow:               "Function.prototype.apply cannot support %0 arguments",
   // SyntaxError
   unable_to_parse:              "Parse error",
   duplicate_regexp_flag:        "Duplicate RegExp flag %0",
   unrecognized_regexp_flag:     "Unrecognized RegExp flag %0",
   invalid_regexp:               "Invalid RegExp pattern /%0/",
@@ skipping 566 matching lines @@
     return this.name + ": " + FormatMessage({ type: type, args: this.arguments });
   }
   var message = this.message;
   return this.name + (message ? (": " + message) : "");
 }, DONT_ENUM);
 
 
 // Boilerplate for exceptions for stack overflows. Used from
 // Top::StackOverflow().
 const kStackOverflowBoilerplate = MakeRangeError('stack_overflow', []);