I think that more information is needed in order to draw such a broad sense of statement about of the Canadian nation. I do think that one element that can be inferred from the scene would be the multi- cultural element to Canadian society. To feature a person not indigenous to the nation marching in a parade that is meant to bolster civic pride speaks to the multiple layers or components in the tapestry of Canadian society. I think that the idea the Hindu woman is carrying a flag for the Quebec nation also highlights some of the challenge that Canada is having in terms of addressing such diversity, as it reflects a movement in Canada that is seeking to keep Quebec as a separate element from the Canadian nation.
When this happens, it makes Canada look like a very cosmopolitan and inclusive nation -- a nation that is very tolerant of diversity.
When this woman marches in a parade for Canada's national day, she is declaring that she identifies herself as a Canadian. She is doing this even though she is not the same ethnicity as most Canadians. This implies that Canada is a country that makes "other" ethnicities feel welcome.
The Quebec flag makes it clear that Canada has a strong federal system that allows people to identify with their own province as well as with the country as a whole.
I believe the Hindu woman carrying the flag is a citizen of Canada and a resident of Quebec.
An occurrence like this shows that that in Canada and particularly in Quebec all the citizens identify themselves as citizens of Canada irrespective of their country of origin and their religion. It further shows that Canada does not discriminate between its citizen based on their race or religion. While this event reflects the feeling of the women carrying the flag. I attach much more significance to the fact that a Hindu women has been chosen by authorities in Quebec to carry the flag in a Canada Day Parade.
I assume, the carrying of Quebec flag was in addition to that of Canadian flag. Therefore I do not attach much significance to the flag itself.