tools/gn: Remove includes of basictypes.h.

tools/gn/substitution_writer.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 TOOLS_GN_SUBSTITUTION_WRITER_H_
 #define TOOLS_GN_SUBSTITUTION_WRITER_H_
 
 #include <iosfwd>
 #include <vector>
 
-#include "base/basictypes.h"
 #include "tools/gn/substitution_type.h"
 
 struct EscapeOptions;
 class OutputFile;
 class Settings;
 class SourceDir;
 class SourceFile;
 class SubstitutionList;
 class SubstitutionPattern;
 class Target;
@@ skipping 199 matching lines @@
   // Like GetSourceSubstitution but for strings based on the target or
   // toolchain. This type of result will always be relative to the build
   // directory.
   static std::string GetLinkerSubstitution(
       const Target* target,
       const Tool* tool,
       SubstitutionType type);
 };
 
 #endif  // TOOLS_GN_SUBSTITUTION_WRITER_H_