Standardize usage of virtual/override/final in gpu/

gpu/command_buffer/client/gles2_trace_implementation.h

 // Copyright (c) 2013 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 GPU_COMMAND_BUFFER_CLIENT_GLES2_TRACE_IMPLEMENTATION_H_
 #define GPU_COMMAND_BUFFER_CLIENT_GLES2_TRACE_IMPLEMENTATION_H_
 
 #include "base/compiler_specific.h"
 #include "gles2_impl_export.h"
 #include "gpu/command_buffer/client/gles2_interface.h"
 
 namespace gpu {
 namespace gles2 {
 
 // GLES2TraceImplementation is calls TRACE for every GL call.
 class GLES2_IMPL_EXPORT GLES2TraceImplementation
     : NON_EXPORTED_BASE(public GLES2Interface) {
  public:
   explicit GLES2TraceImplementation(GLES2Interface* gl);
-  virtual ~GLES2TraceImplementation();
+  ~GLES2TraceImplementation() override;
 
   // Include the auto-generated part of this class. We split this because
   // it means we can easily edit the non-auto generated parts right here in
   // this file instead of having to edit some template or the code generator.
   #include "gpu/command_buffer/client/gles2_trace_implementation_autogen.h"
 
  private:
   GLES2Interface* gl_;
 };
 
 }  // namespace gles2
 }  // namespace gpu
 
 #endif  // GPU_COMMAND_BUFFER_CLIENT_GLES2_TRACE_IMPLEMENTATION_H_