Allow paths to be resolved in the GN args file

tools/gn/setup.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_SETUP_H_
 #define TOOLS_GN_SETUP_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
@@ skipping 133 matching lines @@
 
   bool check_for_bad_items_;
   bool check_for_unused_overrides_;
   bool check_public_headers_;
 
   // See getter for info.
   scoped_ptr<std::vector<LabelPattern>> check_patterns_;
 
   Scheduler scheduler_;
 
-  // These empty settings and toolchain are used to interpret the command line
-  // and dot file.
-  BuildSettings empty_build_settings_;
-  Settings empty_settings_;
+  // These settings and toolchain are used to interpret the command line and
+  // dot file.
+  Settings dotfile_settings_;
   Scope dotfile_scope_;
 
   // State for invoking the dotfile.
   base::FilePath dotfile_name_;
   scoped_ptr<InputFile> dotfile_input_file_;
   std::vector<Token> dotfile_tokens_;
   scoped_ptr<ParseNode> dotfile_root_;
 
   // Set to true when we should populate the build arguments from the command
   // line or build argument file. See setter above.
   bool fill_arguments_;
 
   // State for invoking the command line args. We specifically want to keep
   // this around for the entire run so that Values can blame to the command
   // line when we issue errors about them.
   scoped_ptr<InputFile> args_input_file_;
   std::vector<Token> args_tokens_;
   scoped_ptr<ParseNode> args_root_;
 
   DISALLOW_COPY_AND_ASSIGN(Setup);
 };
 
 #endif  // TOOLS_GN_SETUP_H_