Update {virtual,override} to follow C++11 style in net.

net/disk_cache/blockfile/sparse_control_v3.cc

 // 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.
 
 #include "net/disk_cache/blockfile/sparse_control.h"
 
 #include "base/bind.h"
 #include "base/format_macros.h"
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 38 matching lines @@
 }
 
 // This class deletes the children of a sparse entry.
 class ChildrenDeleter
     : public base::RefCounted<ChildrenDeleter>,
       public disk_cache::FileIOCallback {
  public:
   ChildrenDeleter(disk_cache::BackendImpl* backend, const std::string& name)
       : backend_(backend->GetWeakPtr()), name_(name), signature_(0) {}
 
-  virtual void OnFileIOComplete(int bytes_copied) override;
+  void OnFileIOComplete(int bytes_copied) override;
 
   // Two ways of deleting the children: if we have the children map, use Start()
   // directly, otherwise pass the data address to ReadData().
   void Start(char* buffer, int len);
   void ReadData(disk_cache::Addr address, int len);
 
  private:
   friend class base::RefCounted<ChildrenDeleter>;
-  virtual ~ChildrenDeleter() {}
+  ~ChildrenDeleter() override {}
 
   void DeleteChildren();
 
   base::WeakPtr<disk_cache::BackendImpl> backend_;
   std::string name_;
   disk_cache::Bitmap children_map_;
   int64 signature_;
   scoped_ptr<char[]> buffer_;
   DISALLOW_COPY_AND_ASSIGN(ChildrenDeleter);
 };
@@ skipping 780 matching lines @@
       DoAbortCallbacks();
     return;
   }
 
   // We are running a callback from the message loop. It's time to restart what
   // we were doing before.
   DoChildrenIO();
 }
 
 }  // namespace disk_cache