Switch to standard integer types in tools/.

tools/gn/command_check.cc

 // 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.
 
+#include <stddef.h>
+
 #include "base/command_line.h"
 #include "base/strings/stringprintf.h"
 #include "tools/gn/commands.h"
 #include "tools/gn/header_checker.h"
 #include "tools/gn/setup.h"
 #include "tools/gn/standard_out.h"
 #include "tools/gn/switches.h"
 #include "tools/gn/target.h"
 #include "tools/gn/trace.h"
 
@@ skipping 120 matching lines @@
   header_checker->Run(to_check, force_check, &header_errors);
   for (size_t i = 0; i < header_errors.size(); i++) {
     if (i > 0)
       OutputString("___________________\n", DECORATION_YELLOW);
     header_errors[i].PrintToStdout();
   }
   return header_errors.empty();
 }
 
 }  // namespace commands