Fix ERROR in ShillDeviceClientStub

BUG=none
R=armansito@chromium.org

Review URL: https://codereview.chromium.org/25953006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@227295 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 227295