I don't think that a flagpole by itself counts in calculating the height of a building, but ydoc14 does raise a good point, literally.
The point at which the flag flies, does make it one of the highest flying American flags in the country. Unless, we are proven wrong by someone in Timbuktu. Here is a photo that I took just recently of the Tower of Life Building. The Vistana hugs it in the distance.