replace 'virtual ... OVERRIDE' with '... override'

base/memory/discardable_memory_malloc.h

 // Copyright 2014 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 BASE_MEMORY_DISCARDABLE_MEMORY_MALLOC_H_
 #define BASE_MEMORY_DISCARDABLE_MEMORY_MALLOC_H_
 
 #include "base/memory/discardable_memory.h"
 
 namespace base {
 namespace internal {
 
 class DiscardableMemoryMalloc : public DiscardableMemory {
  public:
   explicit DiscardableMemoryMalloc(size_t size);
   virtual ~DiscardableMemoryMalloc();
 
   bool Initialize();
 
   // Overridden from DiscardableMemory:
-  virtual DiscardableMemoryLockStatus Lock() OVERRIDE;
-  virtual void Unlock() OVERRIDE;
-  virtual void* Memory() const OVERRIDE;
+  DiscardableMemoryLockStatus Lock() override;
+  void Unlock() override;
+  void* Memory() const override;
 
  private:
   scoped_ptr<uint8, FreeDeleter> memory_;
   const size_t size_;
 
   DISALLOW_COPY_AND_ASSIGN(DiscardableMemoryMalloc);
 };
 
 }  // namespace internal
 }  // namespace base
 
 #endif  // BASE_MEMORY_DISCARDABLE_MEMORY_MALLOC_H_