add GCS support to docs server

chrome/common/extensions/docs/server2/cron_servlet_test.py

Index: chrome/common/extensions/docs/server2/cron_servlet_test.py
diff --git a/chrome/common/extensions/docs/server2/cron_servlet_test.py b/chrome/common/extensions/docs/server2/cron_servlet_test.py
index 2dcc34ca666b1822bfd0a5e965c2564bcff56cd8..d54848456f64da804bb85b6d6d6883bd8461d7cd 100755
--- a/chrome/common/extensions/docs/server2/cron_servlet_test.py
+++ b/chrome/common/extensions/docs/server2/cron_servlet_test.py
@@ -13,6 +13,7 @@ from empty_dir_file_system import EmptyDirFileSystem
 from extensions_paths import (
     APP_YAML, CONTENT_PROVIDERS, EXTENSIONS, PUBLIC_TEMPLATES, SERVER2,
     STATIC_DOCS)
+from gcs_file_system_provider import CloudStorageFileSystemProvider
 from github_file_system_provider import GithubFileSystemProvider
 from host_file_system_provider import HostFileSystemProvider
 from local_file_system import LocalFileSystem
@@ -50,6 +51,9 @@ class _TestDelegate(CronServlet.Delegate):
   def CreateGithubFileSystemProvider(self, object_store_creator):
     return GithubFileSystemProvider.ForEmpty()
 
+  def CreateGCSFileSystemProvider(self, object_store_creator):
+    return CloudStorageFileSystemProvider.ForEmpty()
+
   def GetAppVersion(self):
     return self._app_version