Create AllocationSite objects, pointed to by AllocationSiteInfo.

src/heap-snapshot-generator.cc

Index: src/heap-snapshot-generator.cc
diff --git a/src/heap-snapshot-generator.cc b/src/heap-snapshot-generator.cc
index b8237a6b13abaab96c16505c18e44c581729661a..d287b32dc94e6f70e82048ebfafc19b0070384c8 100644
--- a/src/heap-snapshot-generator.cc
+++ b/src/heap-snapshot-generator.cc
@@ -981,6 +981,7 @@ void V8HeapExplorer::ExtractReferences(HeapObject* obj) {
         entry, JSGlobalPropertyCell::cast(obj));
     extract_indexed_refs = false;
   }
+
   if (extract_indexed_refs) {
     SetInternalReference(obj, entry, "map", obj->map(), HeapObject::kMapOffset);
     IndexedReferencesExtractor refs_extractor(this, obj, entry);