Address some comments for class flags

Change-Id: I354f48aefc37ce92c4d02cfce1723db0e28907bf
diff --git a/runtime/mirror/object-inl.h b/runtime/mirror/object-inl.h
index 702a0f4..e35ddcc 100644
--- a/runtime/mirror/object-inl.h
+++ b/runtime/mirror/object-inl.h
@@ -1016,6 +1016,9 @@
     DCHECK(!klass->IsVariableSize());
     VisitInstanceFieldsReferences(klass, visitor);
     DCHECK(!klass->IsClassClass());
+    DCHECK(!klass->IsStringClass());
+    DCHECK(!klass->IsClassLoaderClass());
+    DCHECK(!klass->IsArrayClass());
   } else {
     if ((class_flags & kClassFlagNoReferenceFields) == 0) {
       DCHECK(!klass->IsStringClass());