France committed terrible inhumane crimes in her colonies and never apologised. To this day Africans face racism and are treated differently from French people even if they have the nationality.
However despite all this, there is no reason for burning the infrastructure, robbing stores, stealing cars and making a chaos in France. Tbh they're only proving the stereotypes about Africans to be true (them being violent and uncivilised), not that I agree with them. But they're not helping their situation and only making everything worse for Africans in France.
About the killing of the 17 y/o boy, he clearly didn't deserve the death penalty. He was a criminal and put himself in a situation in which he could've hurt a lot of people and on top of that, tried to run from the police.
The situation could've been dealt with in another way, the police officer could've in the worst case injured him without killing him.
However the police officer was arrested and charged so why are people burning everything in France ? It's really not helping.