What is the significance of the song the woman in the courtyard sings while Winston waits for Julia?

In Part Two, Chapter Four, of 1984,
Winston listens to a prole woman singing a song in the courtyard below his room in Mr
Charrington's shop. While this song appears to have no relevance on the novel, it is, in
fact, significant for two reasons.

First of all, the
dialect of the song has some importance. It is composed in English and makes a
refreshing change to Newspeak, the official language of Oceania. Newspeak is designed to
make thoughtcrime an impossibility because it restricts people's ability to think
negative thoughts about the party. In contrast, English remains expressive and emotive,
even if the song has been composed by a "versificator" and does not technically make any
sense. The song, then, harks back to a time before the party assumed power and this is,
perhaps, the reason for Winston's enjoyment of
it. 

Secondly, the phrase, "opeless fancy," foreshadows the
events to come. At this point in the novel, Winston is still uncertain about the safety
of Mr. Charrington's shop. As he says in the next
scene,

It was
inconceivable that they could frequent this place for more than a few weeks without
being caught.

In this
understanding, it truly is a 'hopeless fancy' that Winston and Julia can ever be safe
from the Thought Police. It is only a matter of time before they are arrested and
imprisoned at the Ministry of Love where all hopes and dreams of rebellion will be
eradicated, once and for all.