This was one of 700 images that popped up on a Flickr search this week because they all had the same sentence 'Entering the second soundstage you pass some of the giant chess pieces from the first movie.' More info from the blurb:-
Warner Bros Studio Tour London: The Making of Harry Potter A great day out for every fan of the boy wizard. The Making of Harry Potter studio tour, covering 150,000 square foot, on two soundstages opened on the 31st March 2012, with stars galore at the red carpet launch at the Leavesden Studios where all eight movies were produced. The home for many film productions, including several James Bond features, before a relatively new production company arrived there to make a film about a young boy who on his 11th birthday discovers he is a wizard.
As far as I can tell, this photo shows the pieces.
Another photo captured the text accompanying the pieces.
THE CHESS PIECES As one of the charms protecting the Philosopher's stone these wizard chessmen were one of director Chris Columbus' favourite elements, and were featured in an iconic scene in the first film. The statues seen here are the original sculptures, many of which were rigged by the special effects team to move by radio control, and even explode.
'They were standing on the edge of a huge chessboard, behind the black chessmen, which were all taller than they were and carved from what looked like black stone.' - J.K. Rowling, Harry Potter and the Sorcerer's Stone
'Exit through the Gift Shop.'