Add simple depends_on API.

recipe_engine/simulation_test.py

 # Copyright 2014-2015 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.
 
 """Provides simulator test coverage for individual recipes."""
 
 import logging
 import re
 import os
 import sys
@@ skipping 56 matching lines @@
       yield expect_tests.Test(
           '%s.%s' % (recipe_name, test_data.name),
           expect_tests.FuncCall(RunRecipe, test_data),
           expect_dir=expect_path,
           expect_base=test_data.name,
           covers=covers,
           break_funcs=(recipe.RunSteps,)
       )
 
 
-def main(package_deps, args=None):
+def main(universe, args=None):
   """Runs simulation tests on a given repo of recipes.
 
   Args:
-    package_deps: a PackageDeps object to operate on
+    universe: a RecipeUniverse object to operate on
     args: command line arguments to expect_tests
   Returns:
     Doesn't -- exits with a status code
   """
   from . import loader
   from . import package
 
   # annotated_run has different behavior when these environment variables
   # are set, so unset to make simulation tests environment-invariant.
   for env_var in ['TESTING_MASTER_HOST',
                   'TESTING_MASTER',
                   'TESTING_SLAVENAME']:
     if env_var in os.environ:
       logging.warn("Ignoring %s environment variable." % env_var)
       os.environ.pop(env_var)
 
   global _UNIVERSE
-  _UNIVERSE = loader.RecipeUniverse(package_deps)
+  _UNIVERSE = universe
 
   expect_tests.main('recipe_simulation_test', GenerateTests,
                     cover_omit=cover_omit(), args=args)