text_area_height (Prawn::Table::Cell)

    # File lib/prawn/table/cell.rb, line 113
          def text_area_height
            text_height = 0
            if @font_size
              @document.font_size(@font_size) do
                text_height = @document.height_of(@text, text_area_width)
              end
            else
              text_height = @document.height_of(@text, text_area_width)
            end
            text_height
          end