Fills the bounding rectangle in bin_window coordinates for the cell at the row specified by @path and the column specified by @column. If @path is %NULL, or points to a path not currently displayed, the @y and @height fields of the rectangle will be filled with 0. If @column is %NULL, the @x and @width fields will be filled with 0. The sum of all cell rects does not cover the entire tree; there are extra pixels in between rows, for example. The returned rectangle is equivalent to the @cell_area passed to gtk_cell_renderer_render(). This function is only valid if @tree_view is realized.