Oilpan: Prepare to move Resource to Oilpan heap.

Source/core/fetch/Resource.h

Index: Source/core/fetch/Resource.h
diff --git a/Source/core/fetch/Resource.h b/Source/core/fetch/Resource.h
index 7bf7326e0742cee313914c41eb43d97965f7cf59..635bcc5ab67d6f57ccb5a75114184cd8d3a9a0ab 100644
--- a/Source/core/fetch/Resource.h
+++ b/Source/core/fetch/Resource.h
@@ -53,8 +53,8 @@ class SharedBuffer;
 // A resource that is held in the cache. Classes who want to use this object should derive
 // from ResourceClient, to get the function calls in case the requested data has arrived.
 // This class also does the actual communication with the loader to obtain the resource from the network.
-class Resource {
-    WTF_MAKE_NONCOPYABLE(Resource); WTF_MAKE_FAST_ALLOCATED;
+class Resource : public NoBaseWillBeGarbageCollectedFinalized<Resource> {
+    WTF_MAKE_NONCOPYABLE(Resource); WTF_MAKE_FAST_ALLOCATED_WILL_BE_REMOVED;
     friend class InspectorResource;
 
 public:
@@ -83,8 +83,16 @@ public:
     };
 
     Resource(const ResourceRequest&, Type);
+#if ENABLE(OILPAN)
     virtual ~Resource();
+#else
+protected:
+    // Only deleteIfPossible should delete this.
+    virtual ~Resource();
+public:
+#endif
     virtual void dispose();
+    virtual void trace(Visitor*);
 
     virtual void load(ResourceFetcher*, const ResourceLoaderOptions&);
 
@@ -378,10 +386,10 @@ private:
     // using HTTP If-Modified-Since/If-None-Match headers. If the response is 304 all clients of this resource are moved
     // to to be clients of m_resourceToRevalidate and the resource is deleted. If not, the field is zeroed and this
     // resources becomes normal resource load.
-    Resource* m_resourceToRevalidate;
+    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).
-    Resource* m_proxyResource;
+    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;