Add recipes to the depgraph command.

recipes.py

 #!/usr/bin/env python
 # Copyright 2015 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.
 
 """Tool to interact with recipe repositories.
 
 This tool operates on the nearest ancestor directory containing an
 infra/config/recipes.cfg.
 """
@@ skipping 192 matching lines @@
     v[project_id] = path
 
 
 def depgraph(package_deps, args):
   from recipe_engine import depgraph
   from recipe_engine import loader
 
   _, config_file = get_package_config(args)
   universe = loader.RecipeUniverse(package_deps, config_file)
 
-  depgraph.main(universe, ignore_packages=args.ignore_package,
-                stdout=args.output)
+  depgraph.main(universe, package_deps.root_package,
+                ignore_packages=args.ignore_package, stdout=args.output)
 
 
 def doc(package_deps, args):
   from recipe_engine import doc
   from recipe_engine import loader
 
   _, config_file = get_package_config(args)
   universe = loader.RecipeUniverse(package_deps, config_file)
 
   doc.main(universe)
@@ skipping 162 matching lines @@
 
     Warmly,
     recipes.py
     """
     return 1
 
   return 0
 
 if __name__ == '__main__':
   sys.exit(main())