Auto merge of #7939 - iawaknahc:issue-7924, r=Manishearth
Auto merge of #7939 - iawaknahc:issue-7924, r=Manishearth

Use typed headers API instead of set_raw

fix https://github.com/servo/servo/issues/7924

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