'Fail silently when a variable\'s dictionary key isn\'t found.'

@setup({'basic-syntax19': '{{    foo.spam    }}'})
def test_basic_syntax19(self):

    output = self.engine.render_to_string('basic-syntax19', {'foo': {'bar': 'baz'}})
    if self.engine.string_if_invalid:
        self.assertEqual(output, 'INVALID')
    else:
        self.assertEqual(output, '')
