fix rowspan assignment for compatibility with Opal
fix rowspan assignment for compatibility with Opal

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