cbuildbot: Add --goma_dir and --goma_client_json options.

These are currently no-op. These are added so that
those flags can be passed from bot recipe to cbuildbot main,
which helps testing via try in following CLs.

BUG=chromium:279618
TEST=Ran "cbuildbot --help" and made sure options are added.

Change-Id: Idc5cac30c533a3e78aa1b2291270b136e3ae9083
Reviewed-on: https://chromium-review.googlesource.com/451338
Commit-Ready: Hidehiko Abe <hidehiko@chromium.org>
Tested-by: Hidehiko Abe <hidehiko@chromium.org>
Reviewed-by: Hidehiko Abe <hidehiko@chromium.org>
diff --git a/scripts/cbuildbot.py b/scripts/cbuildbot.py
index 90cd55a..d8b4685 100644
--- a/scripts/cbuildbot.py
+++ b/scripts/cbuildbot.py
@@ -430,6 +430,17 @@
   parser.add_option('-c', '--config_repo',
                     help='Cloneable path to the git repository containing '
                          'the site configuration to use.')
+  # TODO(crbug.com/279618): Running GOMA is under development. Following
+  # flags are added for development purpose due to repository dependency,
+  # but not officially supported yet.
+  parser.add_option('--goma_dir', type='path',
+                    api=constants.REEXEC_API_GOMA,
+                    help='Specify a directory containing goma. When this is '
+                         'set, GOMA is used to build Chrome.')
+  parser.add_option('--goma_client_json', type='path',
+                    api=constants.REEXEC_API_GOMA,
+                    help='Specify a service-account-goma-client.json path. '
+                         'The file is needed on bots to run GOMA.')
 
   #
   # Patch selection options.