Move SetFastDoubleElementsCapacity into GrowCapacityAndConvert

src/lookup.cc

Index: src/lookup.cc
diff --git a/src/lookup.cc b/src/lookup.cc
index 834870a454eabd85669d2e607210f3aa18ce9861..296d192083a76120b5e5a6697ae8822130f00495 100644
--- a/src/lookup.cc
+++ b/src/lookup.cc
@@ -121,26 +121,10 @@ void LookupIterator::PrepareForDataProperty(Handle<Object> value) {
       JSObject::UpdateAllocationSite(holder, new_kind);
       if (IsFastDoubleElementsKind(old_kind) !=
           IsFastDoubleElementsKind(new_kind)) {
-        Handle<FixedArrayBase> old_elements(holder->elements());
-        int capacity = old_elements->length();
-        Handle<FixedArrayBase> new_elements;
-        if (IsFastDoubleElementsKind(new_kind)) {
-          new_elements = factory()->NewFixedDoubleArray(capacity);
-        } else {
-          new_elements = factory()->NewFixedArray(capacity);
-        }
-
+        uint32_t capacity = holder->elements()->length();
         ElementsAccessor* accessor = ElementsAccessor::ForKind(new_kind);
-        accessor->CopyElements(holder, new_elements, old_kind);
-
-        JSObject::ValidateElements(holder);
-        JSObject::SetMapAndElements(holder, holder_map_, new_elements);
-
-        if (FLAG_trace_elements_transitions) {
-          JSObject::PrintElementsTransition(
-              stdout, holder, old_kind, old_elements, new_kind, new_elements);
-        }
-        // SetMapAndElements above migrated the object. No reloading of property
+        accessor->GrowCapacityAndConvert(holder, capacity);
+        // GrowCapacityAndConvert migrated the object. No reloading of property
         // infomation is necessary for elements.
         return;
       } else if (FLAG_trace_elements_transitions) {