Auto merge of #11909 - nox:wr-nightly, r=Ms2ger
Auto merge of #11909 - nox:wr-nightly, r=Ms2ger

Use nightly feature of webrender_traits

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