Dependency cleanup: moving constants in test.factory to test.env.paths

To allow constants of factory environment (e.g. FACTORY_PATH) be used
in utils, we moved these constants to test.env.paths.
Also, removed redundant FACTORY_PATH defined in py/__init__.py.

Constants have been moved:
  SCRIPT_PATH
  CROS_FACTORY_LIB_PATH
  FACTORY_PATH
  FACTORY_PACKAGE_PATH
  FACTORY_MD4SUM_PATH
  FIRMWARE_UPDATER_PATH
  DEVICE_STATEFUL_PATH
  CHROME_DATA_DIR_NAME

BUG=chromium:403712
TEST=make test, manual test on Chromebook

Change-Id: I7dd85d134e8449ca8f58225404362533a5a973b7
Reviewed-on: https://chromium-review.googlesource.com/321564
Commit-Ready: Wei-Han Chen <stimim@chromium.org>
Tested-by: Wei-Han Chen <stimim@chromium.org>
Reviewed-by: Hung-Te Lin <hungte@chromium.org>
diff --git a/py/gooftool/gooftool.py b/py/gooftool/gooftool.py
index a16a871..80f38a2 100755
--- a/py/gooftool/gooftool.py
+++ b/py/gooftool/gooftool.py
@@ -43,8 +43,8 @@
 from cros.factory.hwid.v3 import common
 from cros.factory.hwid.v3 import hwid_utils
 from cros.factory.test import event_log
-from cros.factory.test import factory
-from cros.factory.test.factory import FACTORY_LOG_PATH, DEVICE_STATEFUL_PATH
+from cros.factory.test.env import paths
+from cros.factory.test.factory import FACTORY_LOG_PATH
 from cros.factory.test.rules.privacy import FilterDict
 from cros.factory.utils import file_utils
 from cros.factory.utils.debug_utils import SetupLogging
@@ -753,9 +753,9 @@
   If that file does not exist (which should only be R30 and earlier),
   this is a no-op.
   """
-  tar_file = os.path.join(DEVICE_STATEFUL_PATH, 'stateful_files.tar.xz')
+  tar_file = os.path.join(paths.DEVICE_STATEFUL_PATH, 'stateful_files.tar.xz')
   if os.path.exists(tar_file):
-    Spawn(['tar', 'xf', tar_file], cwd=DEVICE_STATEFUL_PATH,
+    Spawn(['tar', 'xf', tar_file], cwd=paths.DEVICE_STATEFUL_PATH,
           log=True, check_call=True)
   else:
     logging.warning('No stateful files at %s', tar_file)
@@ -770,7 +770,7 @@
   # 警告:此行会验证工厂软件的完整性,禁止删除或修改。
   event_log.Log(
       'source_hashes',
-      **file_utils.HashSourceTree(os.path.join(factory.FACTORY_PATH, 'py')))
+      **file_utils.HashSourceTree(os.path.join(paths.FACTORY_PATH, 'py')))
 
 
 @Command('log_system_details')