Improve Windows GN build setup.

tools/gn/ninja_binary_target_writer.cc

 // 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.
 
 #include "tools/gn/ninja_binary_target_writer.h"
 
 #include <set>
 
 #include "base/strings/string_util.h"
 #include "tools/gn/config_values_extractors.h"
@@ skipping 77 matching lines @@
 NinjaBinaryTargetWriter::NinjaBinaryTargetWriter(const Target* target,
                                                  std::ostream& out)
     : NinjaTargetWriter(target, out),
       tool_type_(GetToolTypeForTarget(target)){
 }
 
 NinjaBinaryTargetWriter::~NinjaBinaryTargetWriter() {
 }
 
 void NinjaBinaryTargetWriter::Run() {
-  WriteEnvironment();
-
   WriteCompilerVars();
 
   std::vector<OutputFile> obj_files;
   WriteSources(&obj_files);
 
   if (target_->output_type() == Target::SOURCE_SET)
     WriteSourceSetStamp(obj_files);
   else
     WriteLinkerStuff(obj_files);
 }
@@ skipping 344 matching lines @@
     }
 
     // Data files.
     const std::vector<SourceFile>& data = target_->data();
     for (size_t i = 0; i < data.size(); i++) {
       out_ << " ";
       path_output_.WriteFile(out_, data[i]);
     }
   }
 }