Okay. I'm just going to say this.
It doesn't matter that Hinata is on a cover with few other characters. It doesn't matter that Naruto's wearing a scarf and that NaruHina fans are making up whatever theories they want from it. It doesn't even matter Naruto's wearing a scarf in general.
Calm down, people. I know some of us are still anxious since 693 and that the manga's going to end soon, but that's all this is. Shipper fear and paranoia are the only things that are getting to us now.
There is absolutely no reason to be angry or annoyed at seeing Hinata on a cover. We all know she would show up eventually, but still some of us over-react anyway. And if you hate Hinata, then fine. But I see no logical reason why you should interpret a cover as a hint for NaruHina.
Hinata may or may not have a large role in the film, but it will not change NaruSaku's status. For the whole manga series, Naruto's interest in Sakura has been consistent.
Naruto still called Sakura his girlfriend in 631 and did it with Hinata around. After her confession, instead of thinking her over as a possible romantic interest, he spent time with Sakura off missions. Naruto rejected Sakura's confession because he didn't think she was being sincere, not because he feels things for Hinata.
Even with Sakura "confessing" to Sasuke, nothing will change for him. Naruto always believed she loves Sasuke and still made no attempt to move on. Will he start now? The answer is simple. He won't. Naruto has never been deterred by Sakura's feelings for Sasuke. Even if Hinata at some point in the last few chapters throws herself at him again, Naruto still will not like her. Naruto doesn't give up and whatever else Kishi does, he is very consistent in the core of Naruto's character: wanting to be Hokage, wanting Sasuke's acknowledgement, and liking Sakura.
How little we forgot all this just because of NaruSaku paranoia and chapters like 693.
I'd also like to remind you this is just an advertisement. We know absolutely nothing about the plot or the main characters. Hinata may be there just because she's popular.
And if not, for Hinata's role and looking like she's "waiting" ... didn't you notice she looks sad? Have you ever thought maybe she looks like that because Naruto's in a relationship with Sakura or is going to marry her? Have you ever thought her role is in this movie might be closure? Why does everyone have to panic and always jump to negative conclusions? 
And as for the scarf ... I couldn't honestly care less about the scarf. We never saw Naruto wearing a scarf like that in the sketches drawn by Kishimoto so it's looking more to me it's just on this cover because they wanted it there. Most likely means nothing, on both the NaruHina and NaruSaku spectrum.
Everyone, just please don't overthink this. Chances are you're giving yourself more stress than you need to. We don't even know the plot for The Last yet so stop giving yourself heart attacks.
The NaruHina and SasuSaku fans at least know how to keep morale and confidence up. But aren't we the ship with more reason for that? Remember we still have the most development and proof. If NH/SS fans can go around spouting theories with confidence, then I see no reason why we shouldn't.