Fix mixin of patched classes

runtime/vm/object.cc

Index: runtime/vm/object.cc
===================================================================
--- runtime/vm/object.cc	(revision 32974)
+++ runtime/vm/object.cc	(working copy)
@@ -5585,9 +5585,9 @@
   ASSERT(!IsConstructor());
   Function& clone = Function::Handle();
   clone ^= Object::Clone(*this, Heap::kOld);
-  const Class& owner = Class::Handle(this->Owner());
+  const Class& origin = Class::Handle(this->origin());
   const PatchClass& clone_owner =
-      PatchClass::Handle(PatchClass::New(new_owner, owner));
+      PatchClass::Handle(PatchClass::New(new_owner, origin));
   clone.set_owner(clone_owner);
   clone.StorePointer(&clone.raw_ptr()->code_, Code::null());
   clone.StorePointer(&clone.raw_ptr()->unoptimized_code_, Code::null());