Delay resolution of redirecting factory targets in order to avoid class

runtime/vm/class_finalizer.h

Index: runtime/vm/class_finalizer.h
===================================================================
--- runtime/vm/class_finalizer.h	(revision 25531)
+++ runtime/vm/class_finalizer.h	(working copy)
@@ -91,6 +91,10 @@
   // needed during bootstrapping where the classes have been preloaded.
   static void VerifyBootstrapClasses();
 
+  // Resolve the type and target of the redirecting factory.
+  static void ResolveRedirectingFactory(const Class& cls,
+                                        const Function& factory);
+
  private:
   static bool IsSuperCycleFree(const Class& cls);
   static bool IsParameterTypeCycleFree(const Class& cls,