Prevent ThreadableLoaderClient methods from being called after failure notification

Source/core/loader/DocumentThreadableLoader.h

Index: Source/core/loader/DocumentThreadableLoader.h
diff --git a/Source/core/loader/DocumentThreadableLoader.h b/Source/core/loader/DocumentThreadableLoader.h
index 5e768dbe5693f4f60aa52d3bae9e232d78752da3..d2cb23af5e1d52d08eac924739fd36893533bf14 100644
--- a/Source/core/loader/DocumentThreadableLoader.h
+++ b/Source/core/loader/DocumentThreadableLoader.h
@@ -62,6 +62,7 @@ class CORE_EXPORT DocumentThreadableLoader final : public ThreadableLoader, priv
 
         void overrideTimeout(unsigned long timeout) override;
 
+        // |this| may be dead after calling this method in async mode.
         void cancel() override;
         void setDefersLoading(bool);
 
@@ -73,9 +74,16 @@ class CORE_EXPORT DocumentThreadableLoader final : public ThreadableLoader, priv
 
         DocumentThreadableLoader(Document&, ThreadableLoaderClient*, BlockingBehavior, const ResourceRequest&, const ThreadableLoaderOptions&, const ResourceLoaderOptions&);
 
+        void clear();
+
         // ResourceClient
+        //
+        // |this| may be dead after calling this method.
         void notifyFinished(Resource*) override;
+
         // RawResourceClient
+        //
+        // |this| may be dead after calling these methods.
         void dataSent(Resource*, unsigned long long bytesSent, unsigned long long totalBytesToBeSent) override;
         void responseReceived(Resource*, const ResourceResponse&, PassOwnPtr<WebDataConsumerHandle>) override;
         void setSerializedCachedMetadata(Resource*, const char*, size_t) override;
@@ -84,34 +92,49 @@ class CORE_EXPORT DocumentThreadableLoader final : public ThreadableLoader, priv
         void dataDownloaded(Resource*, int) override;
         void didReceiveResourceTiming(Resource*, const ResourceTimingInfo&) override;
 
+        // |this| may be dead after calling this method in async mode.
         void cancelWithError(const ResourceError&);
 
         // Notify Inspector and log to console about resource response. Use
         // this method if response is not going to be finished normally.
         void reportResponseReceived(unsigned long identifier, const ResourceResponse&);
 
-        // Methods containing code to handle resource fetch results which is
+        // Methods containing code to handle resource fetch results which are
         // common to both sync and async mode.
+        //
+        // |this| may be dead after calling these method in async mode.
         void handleResponse(unsigned long identifier, const ResourceResponse&, PassOwnPtr<WebDataConsumerHandle>);
         void handleReceivedData(const char* data, unsigned dataLength);
         void handleSuccessfulFinish(unsigned long identifier, double finishTime);
 
+        // |this| may be dead after calling this method.
         void didTimeout(Timer<DocumentThreadableLoader>*);
         // Calls the appropriate loading method according to policy and data
         // about origin. Only for handling the initial load (including fallback
         // after consulting ServiceWorker).
+        //
+        // |this| may be dead after calling this method in async mode.
         void dispatchInitialRequest(const ResourceRequest&);
+        // |this| may be dead after calling this method in async mode.
         void makeCrossOriginAccessRequest(const ResourceRequest&);
         // Loads m_fallbackRequestForServiceWorker.
+        //
+        // |this| may be dead after calling this method in async mode.
         void loadFallbackRequestForServiceWorker();
         // Loads m_actualRequest.
         void loadActualRequest();
         // Clears m_actualRequest and reports access control check failure to
         // m_client.
+        //
+        // |this| may be dead after calling this method in async mode.
         void handlePreflightFailure(const String& url, const String& errorDescription);
         // Investigates the response for the preflight request. If successful,
         // the actual request will be made later in handleSuccessfulFinish().
+        //
+        // |this| may be dead after calling this method in async mode.
         void handlePreflightResponse(const ResourceResponse&);
+        // |this| may be dead after calling this method.
+        void handleError(const ResourceError&);
 
         void loadRequest(const ResourceRequest&, ResourceLoaderOptions);
         bool isAllowedRedirect(const KURL&) const;