gclient_scm_test.py throws randomly gclient_utils.Error.
Simply update the test expectation. It has no effect on runtime.

BUG=
TEST=


Review URL: http://codereview.chromium.org/7828024

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@99436 0039d316-1c4b-4281-b951-d872f2087c98