Toneri, being a Green-Eyed Monster, has Hinata make him a scarf similar to the one she made for Naruto.
At this point in the story Hinata knows all about Hamura's chakra and its effect of Toneri and his Tenseigan so it's quite possible that she fused Hamura's chakra with the scarf's threads in order to create a Power Nullifier for Toneri. The original plan was probably for him to wear the scarf and be rendered powerless allowing Hinata to rescue Hanabi and destroy the Tenseigan. while he was incapacitated.
After he catches Hinata in the act of trying to destroy the Tenseigan, he destroys most of it, but a small fragment of it remains unscathed and is retrieved by Naruto who carries it with him during the final climactic fight.
In the final fight between Naruto and Toneri, Toneri doesn't use his trademark Chakra Drain on Naruto. Why wouldn't Toneri, a Smug Super, blast him with it first? It's possible that he can't, not yet, because Naruto's scarf fragment its current state acts like a Protective Charm. If he attempts to use his Chakra Drain on Naruto he run the risk of absorbing Hamuras Chakra.
When Naruto delivers his final punch to Toneri he is clearly holding the remains of Hinatas scarf, he concentrates all his chakra on his punch and briefly loses his Six Sages Form as he punches Toneri in the face. Toneri is then blasted across the moon gets stuck in a rock and becomes incapacitated. He can only scream in pain as Hinata gouges her sisters eyes out of his eyesockets.
It's very much possible that Naruto is fusing his own chakra with the scarf chakra in order to bypass Toneris defenses and deliver an Armor-Piercing Attack. He already combined his own Six Sages Chakra with Hinatas Hamura chakra in order to destroy the Tenseigan in a previous scene, so its very much doable.
- Jossed. According to the official novelization of the movie, the scarf was always meant for Naruto, and there's nothing special about it—other than it conveys Hinata's feelings to Naruto and indicating that her fate is tied to Naruto's in the same way as his parents.
There is an exchange between Hinata and Naruto early in the movie in which Naruto offers Hinata to share a cup of ramen at his place. Hinata blushes, becomes flustered and runs away.
The most obvious interpretation of that scene is that Hinata is shocked by the fact that Naruto invited her up to his apartment. However, there is another way to look at this scene:
What if this has been their relationship up until that point?
My guess is that while Hinata loves Naruto, she is very hesitant to take the next step and be with him. She doesnt know how he feels about her (he hasn't answered her Anguished Declaration of Love after all), he is surrounded by fangirls, and the low self-esteem issues that have been plaguing her throughout the duration of the series are still there. She probably thinks that she is not good enough for him, and that he deserves someone better.
On the other side of the equation the scene clearly shows that Naruto, being an Idiot Hero doesnt know how to approach Hinata correctly. Whenever he tries to become more friendly with her, he says something too bold or too Innocently Insensitive which causes her to either become overly flustered or emotionally hurt. He can't understand why she reacts the way she reacts and how she feels about him because he is getting mixed signals from her.
- The very first part of this entry has been Confirmed. Naruto and Hinata are implied to have already been hanging out in the epilogue of Kakashi Hiden, where Hinata openly helps Naruto stand up and actually berates Kakashi after he hit Naruto for spreading a rumor about him and Kahyo. Then, in Chapter 1-Section 7 of Shikamaru Hiden, Sakura confirms that Naruto and Hinata have been "hanging out a lot lately." It should be noted that Kakashi Hiden takes place one year after the War Arc, and Shikamaru Hiden takes place two years after the War Arc, just a few months before the events of this movie. So Naruto and Hinata did develop a stronger friendship after the Fourth Shinobi World War; they just didn't finally get that Relationship Upgrade until this movie.
- Jossed in Konoha Hiden, not that it stops fanfic writers from trying to find a way it could actually happen.