Added retry policy

chrome/browser/chromeos/BUILD.gn

Index: chrome/browser/chromeos/BUILD.gn
diff --git a/chrome/browser/chromeos/BUILD.gn b/chrome/browser/chromeos/BUILD.gn
index f61d1bb74644be762ba39838d69f4dbcb6ddbc7b..430a08e93fac36d327cc5061f42285d44f4214f6 100644
--- a/chrome/browser/chromeos/BUILD.gn
+++ b/chrome/browser/chromeos/BUILD.gn
@@ -1576,12 +1576,19 @@ source_set("unit_tests") {
     "login/auth/cryptohome_authenticator_unittest.cc",
     "login/easy_unlock/easy_unlock_challenge_wrapper_unittest.cc",
     "login/easy_unlock/easy_unlock_tpm_key_manager_unittest.cc",
+    "login/enrollment/enrollment_screen_unittest.cc",
+    "login/enrollment/enterprise_enrollment_helper_mock.cc",
+    "login/enrollment/enterprise_enrollment_helper_mock.h",
+    "login/enrollment/mock_enrollment_screen.cc",
+    "login/enrollment/mock_enrollment_screen.h",

[xiyuan, 2017/02/01 23:01:51]

enterprise_enrollment_helper_mock.*, mock_enrollment_screen.* and
mock_base_screen_delegate.* are included for browser_tests in
chrome/test/BUILD.gn already.

If we want to share the code, we should create a build target to include them
instead of duplicating them.

I am thinking:
1. Add a "test_support" static lib in chrome/browser/chromeos/BUILD.gn
   similar to the "arc_test_support" target there to include those
   shared files.
2. Make browser_tests target in chrome/test/BUILD.gn depends on it,
   i.e. add //chrome/browser/chromeos:test_support to the deps;
3. Make unit_tests target in chrome/browser/chromeos/BUILD.gn also
   depends on it;

     "login/error_screens_histogram_helper_unittest.cc",
     "login/existing_user_controller_auto_login_unittest.cc",
     "login/hwid_checker_unittest.cc",
     "login/profile_auth_data_unittest.cc",
     "login/quick_unlock/pin_storage_unittest.cc",
     "login/saml/saml_offline_signin_limiter_unittest.cc",
+    "login/screens/mock_base_screen_delegate.cc",
+    "login/screens/mock_base_screen_delegate.h",
     "login/signin/merge_session_load_page_unittest.cc",
     "login/supervised/supervised_user_authentication_unittest.cc",
     "login/users/affiliation_unittest.cc",