Add instance counters of Resource and AudioNode, and expose them via WebLeakDetector.

Source/core/fetch/Resource.h

 /*
     Copyright (C) 1998 Lars Knoll (knoll@mpi-hd.mpg.de)
     Copyright (C) 2001 Dirk Mueller <mueller@kde.org>
     Copyright (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
     Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
 
     This library is free software; you can redistribute it and/or
     modify it under the terms of the GNU Library General Public
     License as published by the Free Software Foundation; either
     version 2 of the License, or (at your option) any later version.
@@ skipping 75 matching lines @@
 #if ENABLE(OILPAN)
     virtual ~Resource();
 #else
 protected:
     // Only deleteIfPossible should delete this.
     virtual ~Resource();
 public:
 #endif
     virtual void dispose();
     virtual void trace(Visitor*);
+    static unsigned instanceCount() { return s_instanceCount; }
 
     virtual void load(ResourceFetcher*, const ResourceLoaderOptions&);
 
     virtual void setEncoding(const String&) { }
     virtual String encoding() const { return String(); }
     virtual void appendData(const char*, int);
     virtual void error(Resource::Status);
 
     void setNeedsSynchronousCacheHit(bool needsSynchronousCacheHit) { m_needsSynchronousCacheHit = needsSynchronousCacheHit; }
 
@@ skipping 288 matching lines @@
     RawPtrWillBeMember<Resource> m_resourceToRevalidate;
 
     // If this field is non-null, the resource has a proxy for checking whether it is still up to date (see m_resourceToRevalidate).
     RawPtrWillBeMember<Resource> m_proxyResource;
 
     // These handles will need to be updated to point to the m_resourceToRevalidate in case we get 304 response.
     HashSet<ResourcePtrBase*> m_handlesToRevalidate;
 
     // Ordered list of all redirects followed while fetching this resource.
     Vector<RedirectPair> m_redirectChain;
+
+    static unsigned s_instanceCount;
 };
 
 #if !LOG_DISABLED
 // Intended to be used in LOG statements.
 const char* ResourceTypeName(Resource::Type);
 #endif
 
 #define DEFINE_RESOURCE_TYPE_CASTS(typeName) \
     DEFINE_TYPE_CASTS(typeName##Resource, Resource, resource, resource->type() == Resource::typeName, resource.type() == Resource::typeName); \
     inline typeName##Resource* to##typeName##Resource(const ResourcePtr<Resource>& ptr) { return to##typeName##Resource(ptr.get()); }
 
 }
 
 #endif