fix output for certain edge cases
fix output for certain edge cases

the statements if, for, do, while and with might have an AST_EmptyStatement
as body; if that's the case, we need to make sure that the semicolon gets in
the output.

kemitchell/UglifyJS2,hychen/UglifyJS2,charleslaw/RapydScript-Decompiler,SpainTrain/UglifyJS2,rvanvelzen/UglifyJS2,Jeremy017/UglifyJS2,avdg/UglifyJS2,istr/UglifyJS2,jchbh-duplicate/UglifyJS2,shanaithal/UglifyJS2,dabretin/UglifyJS2,davidbau/UglifyJS2,kittens/UglifyJS2,VIVEKLUCKY1848/UglifyJS2,TrigenSoftware/ColaScript,sahat/UglifyJS2,Venima/Test,shelsonjava/UglifyJS2,GerHobbelt/UglifyJS2,butchi/codedecodeJS,HankMcCoy/UglifyJS2,microlv/UglifyJS2,Spocdoc/uglify-js-fork,supriyantomaftuh/UglifyJS2,beni55/UnuglifyJS,githuboflee/first,sielay/UglifyJS2,vjeux/UglifyJS2,digitalloggers/UglifyJS2,TurkeyFried/uglifyjs2-dist,beni55/UnuglifyJS,tomByrer/UglifyJS2,hxford/UglifyJS2,eth-srl/UnuglifyJS,lautis/UglifyJS2,sebmck/UglifyJS2,eth-srl/UnuglifyJS,butchi/decodecodeJS