[autotest] Teach test_push to test run_suite arguement create_and_return

test_push just tests running suites synchronously but not for asynchronous
suites. Teach to test on flag create_and_return.

BUG=chromium:516461
TEST=Unittest.

Change-Id: I54875cfe2401b378ec0b9e55592284f705ddb755
Reviewed-on: https://chromium-review.googlesource.com/291300
Reviewed-by: Dan Shi <dshi@chromium.org>
Tested-by: Shuqian Zhao <shuqianz@chromium.org>
Commit-Queue: Shuqian Zhao <shuqianz@chromium.org>
diff --git a/site_utils/test_push_unittest.py b/site_utils/test_push_unittest.py
index 4e54030..5e07ca0 100644
--- a/site_utils/test_push_unittest.py
+++ b/site_utils/test_push_unittest.py
@@ -55,7 +55,7 @@
 
         self.mox.StubOutWithMock(test_push, 'do_run_suite')
         test_push.do_run_suite(test_push.PUSH_TO_PROD_SUITE, mox.IgnoreArg(),
-                               mox.IgnoreArg()
+                               mox.IgnoreArg(), mox.IgnoreArg()
                                ).AndReturn((1))
 
         self.mox.StubOutWithMock(site_utils, 'get_test_views_from_tko')