Fix virtual/override/final usage in Source/core/{fetch,loader,streams,xmlhttprequest}/.

Source/core/fetch/LinkFetchResource.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 
 #ifndef LinkFetchResource_h
 #define LinkFetchResource_h
 
 #include "core/fetch/Resource.h"
 #include "core/fetch/ResourceClient.h"
 #include "core/fetch/ResourcePtr.h"
 
 namespace blink {
 
 class FetchRequest;
 class ResourceFetcher;
 
 class LinkFetchResource final : public Resource {
 public:
     typedef ResourceClient ClientType;
 
     static ResourcePtr<Resource> fetch(Resource::Type, FetchRequest&, ResourceFetcher*);
-    virtual ~LinkFetchResource();
+    ~LinkFetchResource() override;
 
 private:
     class LinkResourceFactory : public ResourceFactory {
     public:
         LinkResourceFactory(Resource::Type type)
             : ResourceFactory(type) { }
 
         Resource* create(const ResourceRequest& request, const String& charset) const override
         {
             return new LinkFetchResource(request, type());
         }
     };
     LinkFetchResource(const ResourceRequest&, Type);
 };
 
 }
 
 #endif // LinkFetchResource_h