Standardize usage of virtual/override/final in tools/gn/

tools/gn/setup.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 TOOLS_GN_SETUP_H_
 #define TOOLS_GN_SETUP_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
@@ skipping 72 matching lines @@
 
  private:
   CommonSetup& operator=(const CommonSetup& other);  // Disallow.
 };
 
 // Helper class to setup the build settings and environment for the various
 // commands to run.
 class Setup : public CommonSetup {
  public:
   Setup();
-  virtual ~Setup();
+  ~Setup() override;
 
   // Configures the build for the current command line. On success returns
   // true. On failure, prints the error and returns false.
   //
   // The parameter is the string the user specified for the build directory. We
   // will try to interpret this as a SourceDir if possible, and will fail if is
   // is malformed.
   //
   // With force_create = false, setup will fail if the build directory doesn't
   // alreay exist with an args file in it. With force_create set to true, the
   // directory will be created if necessary. Commands explicitly doing
   // generation should set this to true to create it, but querying commands
   // should set it to false to prevent creating oddly-named directories in case
   // the user omits the build directory argument (which is easy to do).
   bool DoSetup(const std::string& build_dir, bool force_create);
 
   // Runs the load, returning true on success. On failure, prints the error
   // and returns false. This includes both RunPreMessageLoop() and
   // RunPostMessageLoop().
   bool Run();
 
   Scheduler& scheduler() { return scheduler_; }
 
-  virtual Scheduler* GetScheduler() OVERRIDE;
+  Scheduler* GetScheduler() OVERRIDE;
 
   // Returns the file used to store the build arguments. Note that the path
   // might not exist.
   SourceFile GetBuildArgFile() const;
 
   // Sets whether the build arguments should be filled during setup from the
   // command line/build argument file. This will be true by default. The use
   // case for setting it to false is when editing build arguments, we don't
   // want to rely on them being valid.
   void set_fill_arguments(bool fa) { fill_arguments_ = fa; }
@@ skipping 67 matching lines @@
 //   main_setup.Run();
 //   dependent_setup.RunPostMessageLoop();
 // so that the main setup executes the message loop, but both are run.
 class DependentSetup : public CommonSetup {
  public:
   // Note: this could be one function that takes a CommonSetup*, but then
   // the compiler can get confused what to call, since it also matches the
   // default copy constructor.
   DependentSetup(Setup* derive_from);
   DependentSetup(DependentSetup* derive_from);
-  virtual ~DependentSetup();
+  ~DependentSetup() override;
 
   // These are the two parts of Run() in the regular setup, not including the
   // call to actually run the message loop.
   void RunPreMessageLoop();
   bool RunPostMessageLoop();
 
-  virtual Scheduler* GetScheduler() OVERRIDE;
+  Scheduler* GetScheduler() OVERRIDE;
 
  private:
   Scheduler* scheduler_;
 };
 
 #endif  // TOOLS_GN_SETUP_H_