Well, there is no way Sakura will fight for Naruto, she won't behave with Hinata like she did with Ino.
So either Naruto make a move or there is no NaruSaku. That much is certain. It will proof of Sakura's "maturity"
There can't be a love triangle. If there was, it would be in the teaser / trailer.
If they showed Sakura in any trailer showing anything for Naruto then it would not be game over at all. If anything that would be the main sign that NS is it. If Sakura showed any romantic affection for Naruto in the movie, you honestly think Naruto would not pursue it?