Add initial prototype for the GN meta-buildsystem.

tools/gn/ninja_writer.h

Index: tools/gn/ninja_writer.h
diff --git a/tools/gn/ninja_writer.h b/tools/gn/ninja_writer.h
new file mode 100644
index 0000000000000000000000000000000000000000..9b6d2c1dbc210a111ceff33e8ad0ddee6c395d13
--- /dev/null
+++ b/tools/gn/ninja_writer.h
@@ -0,0 +1,27 @@
+// 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_WRITER_H_
+#define TOOLS_GN_NINJA_WRITER_H_
+
+#include "base/basictypes.h"
+
+class BuildSettings;
+
+class NinjaWriter {
+ public:
+  static bool RunAndWriteFiles(const BuildSettings* build_settings);
+
+ private:
+  NinjaWriter(const BuildSettings* build_settings);
+  ~NinjaWriter();
+
+  bool WriteRootBuildfiles();
+
+  const BuildSettings* build_settings_;
+
+  DISALLOW_COPY_AND_ASSIGN(NinjaWriter);
+};
+
+#endif  // TOOLS_GN_NINJA_WRITER_H_