Use the LookupIterator for SetElement and friends

src/runtime/runtime-literals.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 "src/v8.h"
 
 #include "src/allocation-site-scopes.h"
 #include "src/arguments.h"
 #include "src/ast.h"
 #include "src/parser.h"
@@ skipping 76 matching lines @@
           isolate, value,
           CreateLiteralBoilerplate(isolate, literals, array, is_strong),
           Object);
     }
     MaybeHandle<Object> maybe_result;
     uint32_t element_index = 0;
     if (key->IsInternalizedString()) {
       if (Handle<String>::cast(key)->AsArrayIndex(&element_index)) {
         // Array index as string (uint32).
         if (value->IsUninitialized()) value = handle(Smi::FromInt(0), isolate);
-        maybe_result =
-            JSObject::SetOwnElement(boilerplate, element_index, value, SLOPPY);
+        maybe_result = JSObject::SetOwnElementIgnoreAttributes(
+            boilerplate, element_index, value, NONE);
       } else {
         Handle<String> name(String::cast(*key));
         DCHECK(!name->AsArrayIndex(&element_index));
         maybe_result = JSObject::SetOwnPropertyIgnoreAttributes(
             boilerplate, name, value, NONE);
       }
     } else if (key->ToArrayIndex(&element_index)) {
       // Array index (uint32).
       if (value->IsUninitialized()) value = handle(Smi::FromInt(0), isolate);
-      maybe_result =
-          JSObject::SetOwnElement(boilerplate, element_index, value, SLOPPY);
+      maybe_result = JSObject::SetOwnElementIgnoreAttributes(
+          boilerplate, element_index, value, NONE);
     } else {
       // Non-uint32 number.
       DCHECK(key->IsNumber());
       double num = key->Number();
       char arr[100];
       Vector<char> buffer(arr, arraysize(arr));
       const char* str = DoubleToCString(num, buffer);
       Handle<String> name = isolate->factory()->NewStringFromAsciiChecked(str);
       maybe_result = JSObject::SetOwnPropertyIgnoreAttributes(boilerplate, name,
                                                               value, NONE);
@@ skipping 310 matching lines @@
         JSObject::TransitionElementsKind(boilerplate_object, transitioned_kind);
       }
     }
     FixedArray* object_array = FixedArray::cast(object->elements());
     object_array->set(store_index, *value);
   }
   return *object;
 }
 }  // namespace internal
 }  // namespace v8