IBranch.canBeDeleted docstring wrong about subscriptions

IBranch says:

    def canBeDeleted():
        """Can this branch be deleted in its current state.

        A branch is considered deletable if it has no revisions, is not
        linked to any bugs, specs, productseries, or code imports, and
        has no subscribers.
        """

But TestBranchDeletion says:

    def test_subscriptionDoesntDisableDeletion(self):
        """A branch that has a subscription can be deleted."""
        self.branch.subscribe(
            self.user, BranchSubscriptionNotificationLevel.NOEMAIL, None,
            CodeReviewNotificationLevel.NOEMAIL, self.user)
        self.assertEqual(True, self.branch.canBeDeleted())

Only one of those two can be right. I assume the test is correct, so I guess the fix is to remove the “has no subscribers” claim from the canBeDeleted docstring.