2nd half of video is two demonstrations: One for the Burka, and the other (EDL*) against multiculturalism.
This all takes place across the street from the French Embassy, as the Niqab (Islamic face covering) has just been outlawed in France.
* EDL = English Defence League - commonly referred to as Fascists, and who, along with the BNP (British National Party) have a growing support base.
We can assume there are all types in and around both groups. provocateurs, plain clothes etc.
...
The 1st half of the video is a bit of a travel around London with some narrative.