The news of an offer from RM for Cesc appear only in Marca. If you analize the way Marca does business you'd realize that they will "hypothetically" sign the best player of the upcoming rival of Barcelona.
Last week before the game Barca-Atletico, Marca claimed they will sign Kun Aguero, they said they had already reserved the number 10 (Lass current number) for him. They even talked about numbers, just like in this case. Same happened when Barca faced Atlethic Bilbao, in this case with Llorente. Same is happening with Cesc and Arsenal, next rivals of Barcelona in Champions. Same thing will happen the game after when Barca faces Bilbao, they will remember who Llorente is. Marca did a campaign to sign Carlo Ancelotti in 2006 in the CL semifinal against Barca, but like Barca won that game they completely forgot about Ancelotti, unlike Mourinho who did defeat Barca and now he is RM coach.
If Arsenal(along with Cesc) defeats Barca they will continue with their campaign towards signing him cos' "he defeated Barca". If he doesnt(which is most probable) they will resign from that purpose and will forget about all of this. That's how it works
In any case I would bet anything Cesc will not end up in Madrid, all of his family are Barca fanatics and they even profess the independentist tendency.