Preserve the ElementsKind in builtin.cc Slice early return

src/builtins.cc

 // 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.
 
 #include "src/builtins.h"
 
 #include "src/api.h"
 #include "src/api-natives.h"
 #include "src/arguments.h"
 #include "src/base/once.h"
@@ skipping 509 matching lines @@
   // ECMAScript 232, 3rd Edition, Section 15.4.4.10, step 6.
   uint32_t actual_start = (relative_start < 0) ? Max(len + relative_start, 0)
                                                : Min(relative_start, len);
 
   // ECMAScript 232, 3rd Edition, Section 15.4.4.10, step 8.
   uint32_t actual_end =
       (relative_end < 0) ? Max(len + relative_end, 0) : Min(relative_end, len);
 
   if (actual_end <= actual_start) {
     Handle<JSArray> result_array =
-        isolate->factory()->NewJSArray(GetInitialFastElementsKind(), 0, 0);
+        isolate->factory()->NewJSArray(object->GetElementsKind(), 0, 0);
     return *result_array;
   }
 
   ElementsAccessor* accessor = object->GetElementsAccessor();
   if (is_sloppy_arguments &&
       !accessor->IsPacked(object, elms_obj, actual_start, actual_end)) {
     // Don't deal with arguments with holes in C++
     AllowHeapAllocation allow_allocation;
     return CallJsIntrinsic(isolate, isolate->array_slice(), args);
   }
@@ skipping 1533 matching lines @@
 BUILTIN_LIST_C(DEFINE_BUILTIN_ACCESSOR_C)
 BUILTIN_LIST_A(DEFINE_BUILTIN_ACCESSOR_A)
 BUILTIN_LIST_H(DEFINE_BUILTIN_ACCESSOR_H)
 BUILTIN_LIST_DEBUG_A(DEFINE_BUILTIN_ACCESSOR_A)
 #undef DEFINE_BUILTIN_ACCESSOR_C
 #undef DEFINE_BUILTIN_ACCESSOR_A
 
 
 }  // namespace internal
 }  // namespace v8