Auto merge of #8483 - frewsxcv:cleanup-pageiterator-nxt, r=Manishearth
Auto merge of #8483 - frewsxcv:cleanup-pageiterator-nxt, r=Manishearth

Cleanup PageIterator::next

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cbrewster/servo,ConnorGBrewster/servo,nrc/servo,splav/servo,larsbergstrom/servo,paulrouget/servo,notriddle/servo,DominoTree/servo,DominoTree/servo,larsbergstrom/servo,nrc/servo,peterjoel/servo,rnestler/servo,eddyb/servo,saneyuki/servo,cbrewster/servo,paulrouget/servo,pyfisch/servo,rnestler/servo,nnethercote/servo,avadacatavra/servo,SimonSapin/servo,canaltinova/servo,ConnorGBrewster/servo,eddyb/servo,nnethercote/servo,rnestler/servo,saneyuki/servo,pyfisch/servo,avadacatavra/servo,saneyuki/servo,cbrewster/servo,canaltinova/servo,nnethercote/servo,upsuper/servo,emilio/servo,jimberlage/servo,pyfisch/servo,dsandeephegde/servo,larsbergstrom/servo,DominoTree/servo,nrc/servo,dati91/servo,emilio/servo,DominoTree/servo,SimonSapin/servo,ConnorGBrewster/servo,mattnenterprise/servo,mattnenterprise/servo,notriddle/servo,notriddle/servo,CJ8664/servo,peterjoel/servo,paulrouget/servo,upsuper/servo,paulrouget/servo,dati91/servo,jimberlage/servo,cbrewster/servo,eddyb/servo,SimonSapin/servo,KiChjang/servo,sadmansk/servo,steveklabnik/servo,SimonSapin/servo,dati91/servo,thiagopnts/servo,canaltinova/servo,sadmansk/servo,peterjoel/servo,steveklabnik/servo,splav/servo,splav/servo,larsbergstrom/servo,avadacatavra/servo,szeged/servo,KiChjang/servo,paulrouget/servo,nnethercote/servo,emilio/servo,szeged/servo,peterjoel/servo,steveklabnik/servo,eddyb/servo,larsbergstrom/servo,nnethercote/servo,peterjoel/servo,steveklabnik/servo,anthgur/servo,splav/servo,mattnenterprise/servo,nrc/servo,KiChjang/servo,pyfisch/servo,mbrubeck/servo,DominoTree/servo,mbrubeck/servo,paulrouget/servo,ConnorGBrewster/servo,sadmansk/servo,jimberlage/servo,rnestler/servo,splav/servo,canaltinova/servo,nnethercote/servo,nnethercote/servo,pyfisch/servo,notriddle/servo,nnethercote/servo,sadmansk/servo,mbrubeck/servo,dati91/servo,thiagopnts/servo,peterjoel/servo,SimonSapin/servo,jimberlage/servo,szeged/servo,saneyuki/servo,emilio/servo,mattnenterprise/servo,paulrouget/servo,peterjoel/servo,notriddle/servo,ConnorGBrewster/servo,thiagopnts/servo,sadmansk/servo,SimonSapin/servo,ConnorGBrewster/servo,anthgur/servo,avadacatavra/servo,szeged/servo,ConnorGBrewster/servo,emilio/servo,mattnenterprise/servo,splav/servo,rnestler/servo,nnethercote/servo,fiji-flo/servo,steveklabnik/servo,peterjoel/servo,DominoTree/servo,paulrouget/servo,mattnenterprise/servo,dsandeephegde/servo,larsbergstrom/servo,szeged/servo,notriddle/servo,steveklabnik/servo,rnestler/servo,saneyuki/servo,nrc/servo,splav/servo,thiagopnts/servo,avadacatavra/servo,KiChjang/servo,mbrubeck/servo,mbrubeck/servo,larsbergstrom/servo,peterjoel/servo,dati91/servo,emilio/servo,upsuper/servo,nrc/servo,canaltinova/servo,cbrewster/servo,jimberlage/servo,dati91/servo,avadacatavra/servo,thiagopnts/servo,thiagopnts/servo,notriddle/servo,anthgur/servo,CJ8664/servo,emilio/servo,eddyb/servo,KiChjang/servo,CJ8664/servo,dsandeephegde/servo,DominoTree/servo,notriddle/servo,CJ8664/servo,larsbergstrom/servo,jimberlage/servo,anthgur/servo,paulrouget/servo,KiChjang/servo,dsandeephegde/servo,upsuper/servo,larsbergstrom/servo,anthgur/servo,eddyb/servo,eddyb/servo,eddyb/servo,jimberlage/servo,splav/servo,cbrewster/servo,CJ8664/servo,emilio/servo,fiji-flo/servo,KiChjang/servo,larsbergstrom/servo,peterjoel/servo,rnestler/servo,cbrewster/servo,mbrubeck/servo,DominoTree/servo,sadmansk/servo,notriddle/servo,splav/servo,upsuper/servo,szeged/servo,fiji-flo/servo,notriddle/servo,CJ8664/servo,dati91/servo,szeged/servo,canaltinova/servo,emilio/servo,jimberlage/servo,saneyuki/servo,anthgur/servo,sadmansk/servo,upsuper/servo,avadacatavra/servo,sadmansk/servo,thiagopnts/servo,CJ8664/servo,pyfisch/servo,anthgur/servo,nnethercote/servo,dati91/servo,KiChjang/servo,anthgur/servo,KiChjang/servo,avadacatavra/servo,upsuper/servo,thiagopnts/servo,jimberlage/servo,fiji-flo/servo,szeged/servo,paulrouget/servo,cbrewster/servo,splav/servo,mbrubeck/servo,dsandeephegde/servo,pyfisch/servo,KiChjang/servo,dsandeephegde/servo,szeged/servo,pyfisch/servo,SimonSapin/servo,CJ8664/servo,fiji-flo/servo,steveklabnik/servo,mattnenterprise/servo,fiji-flo/servo,fiji-flo/servo,fiji-flo/servo,pyfisch/servo,SimonSapin/servo,upsuper/servo,rnestler/servo,ConnorGBrewster/servo,mattnenterprise/servo,szeged/servo,emilio/servo,canaltinova/servo,mbrubeck/servo,dsandeephegde/servo,saneyuki/servo,nrc/servo,canaltinova/servo,saneyuki/servo,DominoTree/servo,pyfisch/servo,DominoTree/servo,saneyuki/servo,dsandeephegde/servo,saneyuki/servo