Merge 174019 "Make ScriptLoader into a ResourceOwner"

Source/core/fetch/ResourceOwner.h

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 28 matching lines @@
 template<class R, class C = typename R::ClientType>
 class ResourceOwner : public C {
 public:
     typedef R ResourceType;
 
     virtual ~ResourceOwner();
     ResourceType* resource() const { return m_resource.get(); }
 
 protected:
     ResourceOwner();
-    ResourceOwner(const ResourceOwner& other) { setResource(other.resource()); }
+    ResourceOwner(const ResourceOwner& other) { setResource(other.resource(), other.m_subscribing); }
     explicit ResourceOwner(const ResourcePtr<ResourceType>&);
 
-    void setResource(const ResourcePtr<ResourceType>&);
+    void setResource(const ResourcePtr<ResourceType>&, bool subscribing = true);
     void clearResource();
 
     ResourceOwner& operator=(const ResourceOwner& other);
 
 private:
     ResourcePtr<ResourceType> m_resource;
+    bool m_subscribing;
 };
 
 template<class R, class C>
 inline ResourceOwner<R, C>::ResourceOwner()
+    : m_subscribing(false)
 {
 }
 
 template<class R, class C>
 inline ResourceOwner<R, C>::~ResourceOwner()
 {
     clearResource();
 }
 
 template<class R, class C>
 inline ResourceOwner<R, C>::ResourceOwner(const ResourcePtr<R>& resource)
     : m_resource(resource)
 {
     if (m_resource)
         m_resource->addClient(this);
 }
 
 template<class R, class C>
-inline void ResourceOwner<R, C>::setResource(const ResourcePtr<R>& newResource)
+inline void ResourceOwner<R, C>::setResource(const ResourcePtr<R>& newResource, bool subscribe)
 {
     if (newResource == m_resource)
         return;
 
     // Some ResourceClient implementations reenter this so
     // we need to prevent double removal.
     if (ResourcePtr<ResourceType> oldResource = m_resource) {
         m_resource.clear();
-        oldResource->removeClient(this);
+        if (m_subscribing)
+            oldResource->removeClient(this);
     }
 
     if (newResource) {
+        m_subscribing = subscribe;
         m_resource = newResource;
-        m_resource->addClient(this);
+        if (m_subscribing)
+            m_resource->addClient(this);
     }
 }
 
 template<class R, class C>
 inline void ResourceOwner<R, C>::clearResource()
 {
     setResource(0);
 }
 
 template<class R, class C>
 inline ResourceOwner<R, C>& ResourceOwner<R, C>::operator=(const ResourceOwner<R, C>& other)
 {
     if (this == &other)
         return *this;
-    setResource(other.resource());
+    setResource(other.resource(), other.m_subscribing);
     return *this;
 }
 
 } // namespace WebCore
 
 #endif