blink_gc_plugin: retire overloaded traceImpl detection and handling.

tools/clang/blink_gc_plugin/tests/heap/stubs.h

 // 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.
 
 #ifndef HEAP_STUBS_H_
 #define HEAP_STUBS_H_
 
 #include "stddef.h"
 
 #define WTF_MAKE_FAST_ALLOCATED                 \
@@ skipping 258 matching lines @@
 template<typename T>
 class HeapHashCountedSet : public HashCountedSet<T, void, void, HeapAllocator> {
 };
 
 template<typename K, typename V>
 class HeapHashMap : public HashMap<K, V, void, void, void, HeapAllocator> { };
 
 template<typename T>
 class PersistentHeapVector : public Vector<T, 0, HeapAllocator> { };
 
-template <typename Derived>
-class VisitorHelper {
-public:
-    template<typename T>
-    void Trace(const T&);
-};
+class Visitor {
+ public:
+  template <typename T, void (T::*method)(Visitor*)>
+  void RegisterWeakMembers(const T* obj);
 
-class Visitor : public VisitorHelper<Visitor> {
-public:
-    template<typename T, void (T::*method)(Visitor*)>
-    void RegisterWeakMembers(const T* obj);
-};
-
-class InlinedGlobalMarkingVisitor
-    : public VisitorHelper<InlinedGlobalMarkingVisitor> {
-public:
-    InlinedGlobalMarkingVisitor* operator->() { return this; }
-
-    template<typename T, void (T::*method)(Visitor*)>
-    void RegisterWeakMembers(const T* obj);
+  template <typename T>
+  void Trace(const T&);
 };
 
 class GarbageCollectedMixin {
 public:
     virtual void AdjustAndMark(Visitor*) const = 0;
     virtual bool IsHeapObjectAlive(Visitor*) const = 0;
     virtual void Trace(Visitor*) { }
 };
 
 template<typename T>
 struct TraceIfNeeded {
     static void Trace(Visitor*, T*);
 };
 
 }
 
 namespace WTF {
 
 template<typename T>
 struct VectorTraits<blink::Member<T> > {
     static const bool needsDestruction = false;
 };
 
 }
 
 #endif