Make Resource RefCountedWillBeGarbageCollectedFinalized, attempt #2

third_party/WebKit/Source/core/fetch/Resource.h

Index: third_party/WebKit/Source/core/fetch/Resource.h
diff --git a/third_party/WebKit/Source/core/fetch/Resource.h b/third_party/WebKit/Source/core/fetch/Resource.h
index 4558e2feb730d588ae141acd6db72ccd2c0a0826..fb1f31fe4a687103d510adff2a989b614d419429 100644
--- a/third_party/WebKit/Source/core/fetch/Resource.h
+++ b/third_party/WebKit/Source/core/fetch/Resource.h
@@ -49,7 +49,6 @@ struct FetchInitiatorInfo;
 class CachedMetadata;
 class FetchRequest;
 class ResourceClient;
-class ResourcePtrBase;
 class ResourceFetcher;
 class ResourceTimingInfo;
 class InspectorResource;
@@ -60,7 +59,7 @@ 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 CORE_EXPORT Resource : public NoBaseWillBeGarbageCollectedFinalized<Resource> {
+class CORE_EXPORT Resource : public RefCountedWillBeGarbageCollectedFinalized<Resource> {
     WTF_MAKE_NONCOPYABLE(Resource);
     USING_FAST_MALLOC_WITH_TYPE_NAME_WILL_BE_REMOVED(blink::Resource);
     friend class InspectorResource;
@@ -92,16 +91,13 @@ public:
     };
 
     // Exposed for testing.
-    Resource(const ResourceRequest&, Type);
-#if ENABLE(OILPAN)
-    virtual ~Resource();
-#else
-protected:
-    // Only deleteIfPossible should delete this.
+    static PassRefPtrWillBeRawPtr<Resource> create(const ResourceRequest& request, Type type)
+    {
+        return adoptRefWillBeNoop(new Resource(request, type));
+    }
     virtual ~Resource();
-public:
-#endif
-    virtual void dispose();
+
+    virtual void removedFromMemoryCache();
     DECLARE_VIRTUAL_TRACE();
 
     virtual void load(ResourceFetcher*, const ResourceLoaderOptions&);
@@ -141,7 +137,6 @@ public:
     void addClient(ResourceClient*);
     void removeClient(ResourceClient*);
     bool hasClients() const { return !m_clients.isEmpty() || !m_clientsAwaitingCallback.isEmpty() || !m_finishedClients.isEmpty(); }
-    bool deleteIfPossible();
 
     enum PreloadResult {
         PreloadNotReferenced,
@@ -208,8 +203,6 @@ public:
     // This may return nullptr when the resource isn't cacheable.
     CachedMetadataHandler* cacheHandler();
 
-    bool hasOneHandle() const;
-    bool canDelete() const;
     String reasonNotDeletable() const;
 
     // List of acceptable MIME types separated by ",".
@@ -229,9 +222,6 @@ public:
     void increasePreloadCount() { ++m_preloadCount; }
     void decreasePreloadCount() { ASSERT(m_preloadCount); --m_preloadCount; }
 
-    void registerHandle(ResourcePtrBase* h);
-    void unregisterHandle(ResourcePtrBase* h);
-
     bool canReuseRedirectChain();
     bool mustRevalidateDueToCacheHeaders();
     bool canUseCacheValidator();
@@ -245,7 +235,6 @@ public:
     double stalenessLifetime();
 
     bool isPurgeable() const;
-    bool wasPurged() const;
     bool lock();
 
     void setCacheIdentifier(const String& cacheIdentifier) { m_cacheIdentifier = cacheIdentifier; }
@@ -276,38 +265,13 @@ public:
 #endif
 
 protected:
+    Resource(const ResourceRequest&, Type);
+
     virtual void checkNotify();
     virtual void finishOnePart();
 
     virtual void destroyDecodedDataForFailedRevalidation() { }
 
-    // Normal resource pointers will silently switch what Resource* they reference when we
-    // successfully revalidated the resource. We need a way to guarantee that the Resource
-    // that received the 304 response survives long enough to switch everything over to the
-    // revalidatedresource. The normal mechanisms for keeping a Resource alive externally
-    // (ResourcePtrs and ResourceClients registering themselves) don't work in this case, so
-    // have a separate internal protector).
-    class InternalResourcePtr {
-        STACK_ALLOCATED();
-    public:
-        explicit InternalResourcePtr(Resource* resource)
-            : m_resource(resource)
-        {
-            m_resource->incrementProtectorCount();
-        }
-
-        ~InternalResourcePtr()
-        {
-            m_resource->decrementProtectorCount();
-            m_resource->deleteIfPossible();
-        }
-    private:
-        RawPtrWillBeMember<Resource> m_resource;
-    };
-
-    void incrementProtectorCount() { m_protectorCount++; }
-    void decrementProtectorCount() { m_protectorCount--; }
-
     void setEncodedSize(size_t);
     void setDecodedSize(size_t);
     void didAccessDecodedData();
@@ -329,7 +293,7 @@ protected:
         ResourceCallback();
         void runTask();
         OwnPtr<CancellableTaskFactory> m_callbackTaskFactory;
-        WillBeHeapHashSet<RawPtrWillBeMember<Resource>> m_resourcesWithPendingClients;
+        WillBeHeapHashSet<RefPtrWillBeMember<Resource>> m_resourcesWithPendingClients;
     };
 
     bool hasClient(ResourceClient* client) { return m_clients.contains(client) || m_clientsAwaitingCallback.contains(client) || m_finishedClients.contains(client); }
@@ -378,8 +342,6 @@ private:
 
     bool unlock();
 
-    bool hasRightHandleCountApartFromCache(unsigned targetCount) const;
-
     void setCachedMetadata(unsigned dataTypeID, const char*, size_t, CachedMetadataHandler::CacheType);
     void clearCachedMetadata(CachedMetadataHandler::CacheType);
     CachedMetadata* cachedMetadata(unsigned dataTypeID) const;
@@ -401,9 +363,7 @@ private:
 
     size_t m_encodedSize;
     size_t m_decodedSize;
-    unsigned m_handleCount;
     unsigned m_preloadCount;
-    unsigned m_protectorCount;
 
     String m_cacheIdentifier;
 
@@ -412,13 +372,9 @@ private:
 
     unsigned m_loading : 1;
 
-    unsigned m_switchingClientsToRevalidatedResource : 1;
-
     unsigned m_type : 4; // Type
     unsigned m_status : 3; // Status
 
-    unsigned m_wasPurged : 1;
-
     unsigned m_needsSynchronousCacheHit : 1;
     unsigned m_linkPreload : 1;
 
@@ -433,7 +389,7 @@ private:
 class ResourceFactory {
     STACK_ALLOCATED();
 public:
-    virtual Resource* create(const ResourceRequest&, const String&) const = 0;
+    virtual PassRefPtrWillBeRawPtr<Resource> create(const ResourceRequest&, const String&) const = 0;
     Resource::Type type() const { return m_type; }
 
 protected:
@@ -444,7 +400,7 @@ protected:
 
 #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()); }
+    inline typeName##Resource* to##typeName##Resource(const RefPtrWillBeRawPtr<Resource>& ptr) { return to##typeName##Resource(ptr.get()); }
 
 } // namespace blink