Standardize usage of virtual/override/final in net/

net/http/http_stream.h

 // Copyright (c) 2012 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.
 //
 // HttpStream provides an abstraction for a basic http streams, SPDY, and QUIC.
 // The HttpStream subtype is expected to manage the underlying transport
 // appropriately.  For example, a basic http stream will return the transport
 // socket to the pool for reuse.  SPDY streams on the other hand leave the
 // transport socket management to the SpdySession.
 
 #ifndef NET_HTTP_HTTP_STREAM_H_
 #define NET_HTTP_HTTP_STREAM_H_
 
 #include "base/basictypes.h"
 #include "net/base/completion_callback.h"
 #include "net/base/net_export.h"
 #include "net/base/upload_progress.h"
 #include "net/http/http_stream_base.h"
 
 namespace net {
 
 class IOBuffer;
 
 class NET_EXPORT_PRIVATE HttpStream : public HttpStreamBase {
  public:
   HttpStream() {}
-  virtual ~HttpStream() {}
+  ~HttpStream() override {}
 
   // Queries the UploadDataStream for its progress (bytes sent).
   virtual UploadProgress GetUploadProgress() const = 0;
 
   // Returns a new (not initialized) stream using the same underlying
   // connection and invalidates the old stream - no further methods should be
   // called on the old stream.  The caller should ensure that the response body
   // from the previous request is drained before calling this method.  If the
   // subclass does not support renewing the stream, NULL is returned.
   virtual HttpStream* RenewStreamForAuth() = 0;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(HttpStream);
 };
 
 }  // namespace net
 
 #endif  // NET_HTTP_HTTP_STREAM_H_