w2utils.js: XHTML tweak
w2utils.js: XHTML tweak

I don’t know if input.tagName can be null. If it cannot, then the first
condition of the test can be removed.

fosfozol/w2ui,Connum/w2ui,vitmalina/w2ui,cristianofx/w2ui,agzamovr/w2ui,mpf82/w2ui,agzamovr/w2ui,cristianofx/w2ui,ceedriic/w2ui,ceedriic/w2ui,vitmalina/w2ui,fosfozol/w2ui,ceedriic/w2ui,Ebiroll/w2ui,cristianofx/w2ui,agzamovr/w2ui,agzamovr/w2ui,vitmalina/w2ui,Ebiroll/w2ui,Connum/w2ui,fosfozol/w2ui,Ebiroll/w2ui,Connum/w2ui,ceedriic/w2ui,fosfozol/w2ui,aadrian/w2ui,cristianofx/w2ui,cristianofx/w2ui,aadrian/w2ui,mpf82/w2ui,ceedriic/w2ui,mpf82/w2ui,agzamovr/w2ui,mpf82/w2ui,cristianofx/w2ui,aadrian/w2ui,aadrian/w2ui,Ebiroll/w2ui,Ebiroll/w2ui,agzamovr/w2ui,fosfozol/w2ui,Connum/w2ui,agzamovr/w2ui,ceedriic/w2ui,Connum/w2ui,Ebiroll/w2ui,aadrian/w2ui,vitmalina/w2ui,fosfozol/w2ui,aadrian/w2ui,vitmalina/w2ui,Connum/w2ui,vitmalina/w2ui,Connum/w2ui,mpf82/w2ui,mpf82/w2ui,vitmalina/w2ui,fosfozol/w2ui,Ebiroll/w2ui,ceedriic/w2ui,aadrian/w2ui,mpf82/w2ui,cristianofx/w2ui