[loose parser] Use ✖ rather than question mark for placeholders
[loose parser] Use ✖ rather than question mark for placeholders

This way, attempts to re-parse the pretty-printed code won't
be confused by the question marks.

babel/babel,chicoxyzzy/babel,MarcelGerber/acorn,kellyselden/babel,PolymerLabs/babel,samwgoldman/babel,vadzim/babel,blai/acorn-jsx,happibum/acorn,shuhei/babel,babel/babylon,marijnh/acorn,samhou1988/acorn,guybedford/babel,happibum/acorn,maurobringolf/babel,mysticatea/acorn,MarcelGerber/acorn,hulkish/babel,guybedford/babel,maurobringolf/babel,kaicataldo/babel,kaicataldo/babel,thr0w/acorn-jsx,kellyselden/babel,ajaxorg/acorn,hzoo/babel,xiemaisi/acorn,TimothyGu/acorn,CSNW/acorn,samwgoldman/babel,lightscript/babylon-lightscript,gratex/acorn,kellyselden/babel,Rich-Harris/acorn,babel/babel,chicoxyzzy/babel,hzoo/babel,ajaxorg/acorn,mathiasbynens/acorn,xiemaisi/acorn,babel/babel,btmills/acorn,existentialism/babel,TimothyGu/acorn,jridgewell/babel,kaicataldo/babel,jridgewell/babel,luiseduardohdbackup/filbert,Skillupco/babel,claudiopro/babel,TimothyGu/acorn,marijnh/acorn,PolymerLabs/babel,Rich-Harris/acorn,existentialism/babel,luiseduardohdbackup/filbert,RReverser/acorn-jsx,shuhei/babel,differentmatt/filbert,jridgewell/babel,hzoo/babel,kittens/acorn-jsx,kidaa/filbert,maurobringolf/babel,cbishopvelti/babylon,ternjs/acorn,vadzim/babel,mathiasbynens/acorn,gratex/acorn,hulkish/babel,existentialism/babel,Rich-Harris/acorn,kellyselden/babel,differentmatt/filbert,recipesjs/ingredients,babel/babel,kaicataldo/babel,hulkish/babel,ternjs/acorn,samwgoldman/babel,RReverser/biscript,chicoxyzzy/babel,sebmck/acorn-jsx,ajaxorg/acorn,samhou1988/acorn,kidaa/filbert,benekastah/acorn,mysticatea/acorn,Skillupco/babel,danez/babylon,xiemaisi/acorn,claudiopro/babel,btmills/acorn,ternjs/acorn,tonylukasavage/acorn,MarcelGerber/acorn,mysticatea/acorn,marcominetti/acorn-babel,kittens/acorn-jsx,Skillupco/babel,marcominetti/acorn-babel,chicoxyzzy/babel,mathiasbynens/acorn,happibum/acorn,claudiopro/babel,Skillupco/babel,gratex/acorn,guybedford/babel,btmills/acorn,jridgewell/babel,hulkish/babel,sebmck/acorn-jsx,wcjohnson/babylon-lightscript,hzoo/babel,shuhei/babel,PolymerLabs/babel,marijnh/acorn,marcominetti/acorn-babel