Auto merge of #12471 - Ms2ger:script-exec, r=nox
Auto merge of #12471 - Ms2ger:script-exec, r=nox

Cleanup HTMLScriptElement::execute()

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