fix reader test on JRuby 1.9 mode
fix reader test on JRuby 1.9 mode

benignbala/asciidoctor,neontapir/asciidoctor,neontapir/asciidoctor,pepijnve/asciidoctor,mjang/mj-asciidoc,anthonny/asciidoctor,pepijnve/asciidoctor,asciidocfx/asciidoctor,gjtorikian/asciidoctor,mjang/mj-asciidoc,anthonny/asciidoctor,yukisan/asciidoctor,asciidocfx/asciidoctor,benignbala/asciidoctor,glamouracademy/asciidoctor,cuit-zhaxin/asciidoctor,gjtorikian/asciidoctor,yukisan/asciidoctor,cuit-zhaxin/asciidoctor,glamouracademy/asciidoctor