Revert of Remove ExternalArray, derived types, and element kinds

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 34936fb8e8f72dfb43e4c2562d76f57560e7a8f9..63916a268fb237d17afcc1c5ef7eac3b24863b88 100644
--- a/src/heap-snapshot-generator.cc
+++ b/src/heap-snapshot-generator.cc
@@ -856,8 +856,10 @@
     return AddEntry(object, HeapEntry::kHidden, "system / NativeContext");
   } else if (object->IsContext()) {
     return AddEntry(object, HeapEntry::kObject, "system / Context");
-  } else if (object->IsFixedArray() || object->IsFixedDoubleArray() ||
-             object->IsByteArray()) {
+  } else if (object->IsFixedArray() ||
+             object->IsFixedDoubleArray() ||
+             object->IsByteArray() ||
+             object->IsExternalArray()) {
     return AddEntry(object, HeapEntry::kArray, "");
   } else if (object->IsHeapNumber()) {
     return AddEntry(object, HeapEntry::kHeapNumber, "number");