recipe_engine: change resource API to use repo root

recipe_engine/recipe_api.py

Index: recipe_engine/recipe_api.py
diff --git a/recipe_engine/recipe_api.py b/recipe_engine/recipe_api.py
index 920cfb580be48e07c6ba9760681185d5926c25fa..28fd9dc20c959dcb84ef81318a79ed32afb1e954 100644
--- a/recipe_engine/recipe_api.py
+++ b/recipe_engine/recipe_api.py
@@ -446,11 +446,11 @@ class RecipeApiPlain(object):
     #  module.resource('dir').join('subdir', 'file.py')
     return self._module.MODULE_DIRECTORY.join('resources', *path)
 
-  def package_resource(self, *path):
+  def package_repo_resource(self, *path):
     """Returns a resource path, where path is relative to the root of
-    the package where this module is defined.
+    the package repo where this module is defined.
     """
-    return self._module.PACKAGE_DIRECTORY.join(*path)
+    return self._module.PACKAGE_REPO_ROOT.join(*path)
 
   @property
   def name(self):