Add use-chromium-style-naming option to Blink GC plugin.

tools/clang/blink_gc_plugin/tests/legacy_naming/trace_if_needed.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 TRACE_IF_NEEDED_H_
 #define TRACE_IF_NEEDED_H_
 
 #include "heap/stubs.h"
 
 namespace blink {
 
 class HeapObject : public GarbageCollected<HeapObject> { };
 
 template<typename T>
 class TemplatedObject : public GarbageCollected<TemplatedObject<T> > {
 public:
     virtual void trace(Visitor*);
 private:
     T m_one;
     T m_two;
 };
 
 class InstantiatedObject : public TemplatedObject<Member<HeapObject> > { };
 
 }
 
 #endif