Properly handle holes following spreads in array literals

src/ast/ast-value-factory.h

 // Copyright 2014 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 278 matching lines @@
   F(dot_generator_object, ".generator_object")  \
   F(dot_iterator, ".iterator")                  \
   F(dot_promise, ".promise")                    \
   F(dot_result, ".result")                      \
   F(dot_switch_tag, ".switch_tag")              \
   F(dot_catch, ".catch")                        \
   F(empty, "")                                  \
   F(eval, "eval")                               \
   F(function, "function")                       \
   F(get_space, "get ")                          \
+  F(length, "length")                           \
   F(let, "let")                                 \
   F(native, "native")                           \
   F(new_target, ".new.target")                  \
   F(next, "next")                               \
   F(proto, "__proto__")                         \
   F(prototype, "prototype")                     \
   F(return, "return")                           \
   F(set_space, "set ")                          \
   F(star_default_star, "*default*")             \
   F(this, "this")                               \
@@ skipping 126 matching lines @@
   OTHER_CONSTANTS(F)
 #undef F
 };
 }  // namespace internal
 }  // namespace v8
 
 #undef STRING_CONSTANTS
 #undef OTHER_CONSTANTS
 
 #endif  // V8_AST_AST_VALUE_FACTORY_H_