Move builders.py and steps.py to chromium_tests.

scripts/slave/recipe_modules/chromium/api.py

Index: scripts/slave/recipe_modules/chromium/api.py
diff --git a/scripts/slave/recipe_modules/chromium/api.py b/scripts/slave/recipe_modules/chromium/api.py
index caea92bccf1bb4e179b7b1eadb39eec46316421d..18dac4f2d900de2ba5a992f0e3a1f35e5f57bc24 100644
--- a/scripts/slave/recipe_modules/chromium/api.py
+++ b/scripts/slave/recipe_modules/chromium/api.py
@@ -7,9 +7,6 @@ import re
 from recipe_engine import recipe_api
 from recipe_engine import util as recipe_util
 
-from . import builders
-from . import steps
-
 class TestLauncherFilterFileInputPlaceholder(recipe_util.Placeholder):
   def __init__(self, api, tests):
     self.raw = api.m.raw_io.input('\n'.join(tests))
@@ -30,7 +27,6 @@ class ChromiumApi(recipe_api.RecipeApi):
     super(ChromiumApi, self).__init__(*args, **kwargs)
     self._build_properties = None
     self._builders = {}
-    self.add_builders(builders.BUILDERS)
 
   def get_config_defaults(self):
     return {
@@ -73,10 +69,6 @@ class ChromiumApi(recipe_api.RecipeApi):
     return self._builders
 
   @property
-  def steps(self):
-    return steps
-
-  @property
   def build_properties(self):
     return self._build_properties