Make the Mac build work.

tools/gn/input_file.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_INPUT_FILE_H_
 #define TOOLS_GN_INPUT_FILE_H_
 
 #include <string>
 
 #include "base/basictypes.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "tools/gn/source_dir.h"
 #include "tools/gn/source_file.h"
 
 class InputFile {
  public:
   InputFile(const SourceFile& name);
 
-  // Constructor for testing. Uses an empty file path and a given contents.
-  //InputFile(const char* contents);
   ~InputFile();
 
+  // The virtual name passed into the constructor. This does not take into
+  // account whether the file was loaded from the secondary source tree (see
+  // BuildSettings secondary_source_path).
   const SourceFile& name() const { return name_; }
 
-  // The directory is just a cached version of name_->GetDir() but we get this
+  // The directory is just a cached version of name()->GetDir() but we get this
   // a lot so computing it once up front saves a bunch of work.
   const SourceDir& dir() const { return dir_; }
 
+  // The physical name tells the actual name on disk, if there is one.
+  const base::FilePath& physical_name() const { return physical_name_; }
+
   const std::string& contents() const {
     DCHECK(contents_loaded_);
     return contents_;
   }
 
   // For testing and in cases where this input doesn't actually refer to
   // "a file".
   void SetContents(const std::string& c);
 
   // Loads the given file synchronously, returning true on success. This
   bool Load(const base::FilePath& system_path);
 
  private:
   SourceFile name_;
   SourceDir dir_;
 
+  base::FilePath physical_name_;
+
   bool contents_loaded_;
   std::string contents_;
 
   DISALLOW_COPY_AND_ASSIGN(InputFile);
 };
 
 #endif  // TOOLS_GN_INPUT_FILE_H_