[OE-core] Setting SRC_URI via anonymous Python fails in OE 2.1

[Andre McCurdy]

The following works in OE 2.0, but fails in 2.1 and master:

  python () {
      d.setVar("SRC_URI_FOO", "http://foo.com/foo.tgz")
  }

  SRC_URI = "${SRC_URI_FOO}"


Is it a regression or was something like that never intended to work?