Build API: Standardize return codes.

BUG=chromium:963605
TEST=run_tests

Change-Id: If05654fe56e24425da1b89b8d516cc7ba6bebd3f
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/1615507
Tested-by: Alex Klein <saklein@chromium.org>
Tested-by: David Burger <dburger@chromium.org>
Commit-Queue: Alex Klein <saklein@chromium.org>
Reviewed-by: David Burger <dburger@chromium.org>
Reviewed-by: Evan Hernandez <evanhernandez@chromium.org>
diff --git a/api/controller/test_unittest.py b/api/controller/test_unittest.py
index 48a151b..f831a8e 100644
--- a/api/controller/test_unittest.py
+++ b/api/controller/test_unittest.py
@@ -9,6 +9,7 @@
 
 import mock
 
+from chromite.api import controller
 from chromite.api.controller import test as test_controller
 from chromite.api.gen.chromiumos import common_pb2
 from chromite.api.gen.chromite.api import image_pb2
@@ -83,7 +84,7 @@
 
     rc = test_controller.BuildTargetUnitTest(input_msg, output_msg)
 
-    self.assertNotEqual(0, rc)
+    self.assertEqual(controller.RETURN_CODE_UNSUCCESSFUL_RESPONSE_AVAILABLE, rc)
     self.assertTrue(output_msg.failed_packages)
     failed = []
     for pi in output_msg.failed_packages:
@@ -110,7 +111,7 @@
 
     rc = test_controller.BuildTargetUnitTest(input_msg, output_msg)
 
-    self.assertNotEqual(0, rc)
+    self.assertEqual(controller.RETURN_CODE_UNSUCCESSFUL_RESPONSE_AVAILABLE, rc)
     self.assertTrue(output_msg.failed_packages)
     failed = []
     for pi in output_msg.failed_packages:
@@ -137,7 +138,7 @@
 
     rc = test_controller.BuildTargetUnitTest(input_msg, output_msg)
 
-    self.assertNotEqual(0, rc)
+    self.assertEqual(controller.RETURN_CODE_COMPLETED_UNSUCCESSFULLY, rc)
     self.assertFalse(output_msg.failed_packages)
     patch.assert_called_with(constants.SOURCE_ROOT, 'board', extra_env=mock.ANY,
                              chroot_args=mock.ANY, build_stage=False,