[compiler] Promote ObjectDataKind::kBackgroundSerializedHeapObject

So far this kind was used only when concurrent inlining was enabled.
With this CL we always use it (for the corresponding objects).

This change has probably little effect but is one step towards the
"final" configuration.

Bug: v8:7790
Change-Id: Id56908382b2cd57e2f85246c814fb58aaea6b3c9
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3030712
Auto-Submit: Georg Neis <neis@chromium.org>
Reviewed-by: Nico Hartmann <nicohartmann@chromium.org>
Commit-Queue: Nico Hartmann <nicohartmann@chromium.org>
Cr-Commit-Position: refs/heads/master@{#75759}

src/compiler/heap-refs.cc

@@ -679,7 +679,6 @@ class JSDataViewData : public JSObjectData {
       byte_length_ = object->byte_length();
     } else {
       DCHECK_EQ(kind, kBackgroundSerializedHeapObject);
-      DCHECK(broker->is_concurrent_inlining());
     }
   }
 
@@ -2256,20 +2255,14 @@ struct CreateDataFunctor<RefSerializationKind::kBackgroundSerialized, DataT,
                          ObjectT> {
   bool operator()(JSHeapBroker* broker, RefsMap* refs, Handle<Object> object,
                   RefsMap::Entry** entry_out, ObjectData** object_data_out) {
-    if (broker->is_concurrent_inlining()) {
+    if (broker->is_concurrent_inlining() ||
+        broker->mode() == JSHeapBroker::kSerializing) {
       RefsMap::Entry* entry = refs->LookupOrInsert(object.address());
       *object_data_out = broker->zone()->New<DataT>(
           broker, &entry->value, Handle<ObjectT>::cast(object),
           kBackgroundSerializedHeapObject);
       *entry_out = entry;
       return true;
-    } else if (broker->mode() == JSHeapBroker::kSerializing) {
-      RefsMap::Entry* entry = refs->LookupOrInsert(object.address());
-      *object_data_out = broker->zone()->New<DataT>(
-          broker, &entry->value, Handle<ObjectT>::cast(object),
-          ObjectDataKind::kSerializedHeapObject);
-      *entry_out = entry;
-      return true;
     }
     return false;
   }