gc plugin: remove ScriptWrappable destructor special case.

tools/clang/blink_gc_plugin/tests/class_requires_finalization_base.cpp

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "class_requires_finalization_base.h"
 
 namespace blink {
 
 void NeedsFinalizer::trace(Visitor* visitor)
 {
     A::trace(visitor);
 }
 
 void DoesNotNeedFinalizer::trace(Visitor* visitor)
 {
     A::trace(visitor);
 }
 
-void GCedClassWithAScriptWrappableBase::trace(Visitor* visitor)
-{
-    A::trace(visitor);
 }
-
-void GCedClassWithAScriptWrappableAndAFinalizableBase::trace(Visitor* visitor)
-{
-    GCedClassWithAScriptWrappableBase::trace(visitor);
-}
-
-}