[cleanup] Remove unused root empty_property_cell

Change-Id: I702f8c021490f0538a98cad9a61b1dbae60fb881
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2649027Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72314}

src/heap/setup-heap-internal.cc

@@ -931,13 +931,6 @@ void Heap::CreateInitialObjects() {
   script->set_origin_options(ScriptOriginOptions(true, false));
   set_empty_script(*script);
 
-  {
-    Handle<PropertyCell> cell = factory->NewPropertyCell(
-        factory->empty_string(), AllocationType::kReadOnly);
-    cell->set_value(roots.the_hole_value());
-    set_empty_property_cell(*cell);
-  }
-
   // Protectors
   {
     Handle<PropertyCell> cell =

src/roots/roots.h

@@ -163,7 +163,6 @@ class Symbol;
   V(OrderedHashMap, empty_ordered_hash_map, EmptyOrderedHashMap)               \
   V(OrderedHashSet, empty_ordered_hash_set, EmptyOrderedHashSet)               \
   V(FeedbackMetadata, empty_feedback_metadata, EmptyFeedbackMetadata)          \
-  V(PropertyCell, empty_property_cell, EmptyPropertyCell)                      \
   V(NameDictionary, empty_property_dictionary, EmptyPropertyDictionary)        \
   V(OrderedNameDictionary, empty_ordered_property_dictionary,                  \
     EmptyOrderedPropertyDictionary)                                            \