[builtins] move String.prototype[@@iterator] to C++ builtin

src/compiler/types.cc

 // Copyright 2014 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.
 
 #include <iomanip>
 
 #include "src/compiler/types.h"
 
 #include "src/handles-inl.h"
 #include "src/ostreams.h"
@@ skipping 196 matching lines @@
     case JS_GENERATOR_OBJECT_TYPE:
     case JS_ARRAY_BUFFER_TYPE:
     case JS_ARRAY_TYPE:
     case JS_REGEXP_TYPE:  // TODO(rossberg): there should be a RegExp type.
     case JS_TYPED_ARRAY_TYPE:
     case JS_DATA_VIEW_TYPE:
     case JS_SET_TYPE:
     case JS_MAP_TYPE:
     case JS_SET_ITERATOR_TYPE:
     case JS_MAP_ITERATOR_TYPE:
+    case JS_STRING_ITERATOR_TYPE:
     case JS_WEAK_MAP_TYPE:
     case JS_WEAK_SET_TYPE:
     case JS_PROMISE_TYPE:
     case JS_BOUND_FUNCTION_TYPE:
       DCHECK(!map->is_undetectable());
       return kOtherObject;
     case JS_FUNCTION_TYPE:
       DCHECK(!map->is_undetectable());
       return kFunction;
     case JS_PROXY_TYPE:
@@ skipping 885 matching lines @@
 }
 
 // -----------------------------------------------------------------------------
 // Instantiations.
 
 template class Type::Iterator<i::Object>;
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8