percent_line

# File lib/erb.rb, line 407
      def percent_line(line, &block)
        if @stag || line[0] != %%
          return @scan_line.call(line, &block)
        end

        line[0] = ''
        if line[0] == %%
          @scan_line.call(line, &block)
        else
          yield(PercentLine.new(line.chomp))
        end
      end