GN: Move towards only using / on Windows

tools/gn/ninja_toolchain_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_toolchain_writer.h"
 
 #include <fstream>
 
 #include "base/file_util.h"
 #include "base/strings/stringize_macros.h"
 #include "tools/gn/build_settings.h"
 #include "tools/gn/settings.h"
 #include "tools/gn/target.h"
 #include "tools/gn/toolchain.h"
 #include "tools/gn/trace.h"
 
 NinjaToolchainWriter::NinjaToolchainWriter(
     const Settings* settings,
     const Toolchain* toolchain,
     const std::vector<const Target*>& targets,
     std::ostream& out)
     : settings_(settings),
       toolchain_(toolchain),
       targets_(targets),
       out_(out),
-      path_output_(settings_->build_settings()->build_dir(),
-                   ESCAPE_NINJA, true),
-      helper_(settings->build_settings()) {
-}
+      path_output_(settings_->build_settings()->build_dir(), ESCAPE_NINJA),
+      helper_(settings->build_settings()) {}
 
 NinjaToolchainWriter::~NinjaToolchainWriter() {
 }
 
 void NinjaToolchainWriter::Run() {
   WriteRules();
   WriteSubninjas();
 }
 
 // static
@@ skipping 54 matching lines @@
 void NinjaToolchainWriter::WriteSubninjas() {
   // Write subninja commands for each generated target.
   for (size_t i = 0; i < targets_.size(); i++) {
     OutputFile ninja_file = helper_.GetNinjaFileForTarget(targets_[i]);
     out_ << "subninja ";
     path_output_.WriteFile(out_, ninja_file);
     out_ << std::endl;
   }
   out_ << std::endl;
 }