depot_tools: only add mock infra_paths when test data is enabled

recipe_modules/infra_paths/api.py

 # Copyright 2016 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.
 
 from recipe_engine import recipe_api
 from recipe_engine.config_types import Path, NamedBasePath
 
 
 class InfraPathsApi(recipe_api.RecipeApi):
   def get_config_defaults(self):
@@ skipping 11 matching lines @@
     if self._config_set:
       return
     self._config_set = True
 
     path_config = self.m.properties.get('path_config')
     if path_config in ('kitchen',):
       self.set_config(path_config)
     else:
       self.set_config('buildbot')
 
-    for path in self._test_data.get('exists', []):
-      assert isinstance(path.base, NamedBasePath)
-      self.m.path.mock_add_paths(self[path.base.name].join(*path.pieces))
+    if self._test_data.enabled:
+      for path in self._test_data.get('exists', []):
+        assert isinstance(path.base, NamedBasePath)
+        self.m.path.mock_add_paths(self[path.base.name].join(*path.pieces))
 
   def __getitem__(self, name):
     self._lazy_set_config()
     return self.c.paths[name]