Revert 232657 "GN: toolchain threading cleanup"

trunk/src/tools/gn/ninja_script_target_writer.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_NINJA_SCRIPT_TARGET_WRITER_H_
 #define TOOLS_GN_NINJA_SCRIPT_TARGET_WRITER_H_
 
 #include <vector>
 
 #include "base/compiler_specific.h"
 #include "base/gtest_prod_util.h"
 #include "tools/gn/ninja_target_writer.h"
 
 class FileTemplate;
 class OutputFile;
 
 // Writes a .ninja file for a custom script target type.
 class NinjaScriptTargetWriter : public NinjaTargetWriter {
  public:
-  NinjaScriptTargetWriter(const Target* target,
-                          const Toolchain* toolchain,
-                          std::ostream& out);
+  NinjaScriptTargetWriter(const Target* target, std::ostream& out);
   virtual ~NinjaScriptTargetWriter();
 
   virtual void Run() OVERRIDE;
 
  private:
   FRIEND_TEST_ALL_PREFIXES(NinjaScriptTargetWriter,
                            WriteOutputFilesForBuildLine);
   FRIEND_TEST_ALL_PREFIXES(NinjaScriptTargetWriter,
                            WriteArgsSubstitutions);
 
@@ skipping 34 matching lines @@
 
   // Path output writer that doesn't do any escaping or quoting. It does,
   // however, convert slashes.  Used for
   // computing intermediate strings.
   PathOutput path_output_no_escaping_;
 
   DISALLOW_COPY_AND_ASSIGN(NinjaScriptTargetWriter);
 };
 
 #endif  // TOOLS_GN_NINJA_SCRIPT_TARGET_WRITER_H_