Auto merge of #5752 - Ms2ger:cx-immutable, r=jdm
Auto merge of #5752 - Ms2ger:cx-immutable, r=jdm

Since we drop the ScriptTask almost immediately after clearing the field,
there's little reason to do it manually.

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nerith/servo,aweinstock314/servo,akosel/servo,SimonSapin/servo,karlito40/servo,jimberlage/servo,tschneidereit/servo,notriddle/servo,KiChjang/servo,avadacatavra/servo,bjwbell/servo,notriddle/servo,boghison/servo,tempbottle/servo,youprofit/servo,vks/servo,meh/servo,cbrewster/servo,jimberlage/servo,avadacatavra/servo,brendandahl/servo,nrc/servo,dati91/servo,rixrix/servo,fiji-flo/servo,boghison/servo,karlito40/servo,tafia/servo,boghison/servo,mt2d2/servo,rixrix/servo,canaltinova/servo,emilio/servo,anthgur/servo,ConnorGBrewster/servo,pgonda/servo,jdramani/servo,A-deLuna/servo,thiagopnts/servo,GyrosOfWar/servo,rixrix/servo,kindersung/servo,nnethercote/servo,canaltinova/servo,codemac/servo,brendandahl/servo,tempbottle/servo,tschneidereit/servo,huonw/servo,akosel/servo,jdramani/servo,upsuper/servo,brendandahl/servo,upsuper/servo,sadmansk/servo,pyecs/servo,codemac/servo,nick-thompson/servo,A-deLuna/servo,deokjinkim/servo,walac/servo,zhangjunlei26/servo,CJ8664/servo,jlegendary/servo,runarberg/servo,mt2d2/servo,mattnenterprise/servo,mbrubeck/servo,paulrouget/servo,jlegendary/servo,rixrix/servo,mbrubeck/servo,dati91/servo,mdibaiee/servo,splav/servo,dhananjay92/servo,s142857/servo,walac/servo,sadmansk/servo,nerith/servo,wartman4404/servo,fiji-flo/servo,notriddle/servo,ConnorGBrewster/servo,szeged/servo,youprofit/servo,notriddle/servo,dhananjay92/servo,j3parker/servo,nnethercote/servo,canaltinova/servo,ryancanhelpyou/servo,walac/servo,splav/servo,saneyuki/servo,karlito40/servo,pyfisch/servo,paulrouget/servo,thiagopnts/servo,wpgallih/servo,AnthonyBroadCrawford/servo,aweinstock314/servo,deokjinkim/servo,dvberkel/servo,RenaudParis/servo,rnestler/servo,GreenRecycleBin/servo,ryancanhelpyou/servo,zentner-kyle/servo,wartman4404/servo,tschneidereit/servo,kindersung/servo,dhananjay92/servo,tempbottle/servo,saneyuki/servo,SimonSapin/servo,akosel/servo,j3parker/servo,vks/servo,canaltinova/servo,nrc/servo,szeged/servo,AnthonyBroadCrawford/servo,walac/servo,steveklabnik/servo,runarberg/servo,larsbergstrom/servo,AnthonyBroadCrawford/servo,nrc/servo,evilpie/servo,meh/servo,GyrosOfWar/servo,mdibaiee/servo,mattnenterprise/servo,pyfisch/servo,runarberg/servo,szeged/servo,j3parker/servo,dsandeephegde/servo,caldwell/servo,nick-thompson/servo,DominoTree/servo,pyfisch/servo,DominoTree/servo,youprofit/servo,dagnir/servo,youprofit/servo,paulrouget/servo,g-k/servo,hyowon/servo,peterjoel/servo,avadacatavra/servo,jdramani/servo,deokjinkim/servo,tempbottle/servo,zentner-kyle/servo,splav/servo,tschneidereit/servo,walac/servo,jgraham/servo,nrc/servo,pyecs/servo,peterjoel/servo,pgonda/servo,peterjoel/servo,emilio/servo,GyrosOfWar/servo,eddyb/servo,dvberkel/servo,pyfisch/servo,dsandeephegde/servo,szeged/servo,dvberkel/servo,splav/servo,paulrouget/servo,rentongzhang/servo,dvberkel/servo,evilpie/servo,SimonSapin/servo,KiChjang/servo,eddyb/servo,canaltinova/servo,emilio/servo,dsandeephegde/servo,szeged/servo,nick-thompson/servo,wartman4404/servo,KiChjang/servo,youprofit/servo,fiji-flo/servo,zhangjunlei26/servo,cbrewster/servo,g-k/servo,dagnir/servo,rnestler/servo,ConnorGBrewster/servo,boghison/servo,dvberkel/servo,mattnenterprise/servo,thiagopnts/servo,CJ8664/servo,canaltinova/servo,GreenRecycleBin/servo,samfoo/servo,dsandeephegde/servo,saneyuki/servo,avadacatavra/servo,bjwbell/servo,upsuper/servo,wartman4404/servo,wpgallih/servo,SimonSapin/servo,splav/servo,thiagopnts/servo,peterjoel/servo,notriddle/servo,huonw/servo,samfoo/servo,GyrosOfWar/servo,wpgallih/servo,GyrosOfWar/servo,SimonSapin/servo,RenaudParis/servo,j3parker/servo,GreenRecycleBin/servo,SimonSapin/servo,larsbergstrom/servo,walac/servo,tafia/servo,pyfisch/servo,saratang/servo,pgonda/servo,dati91/servo,sadmansk/servo,steveklabnik/servo,peterjoel/servo,A-deLuna/servo,s142857/servo,pyfisch/servo,szeged/servo,vks/servo,evilpie/servo,anthgur/servo,KiChjang/servo,mbrubeck/servo,zhangjunlei26/servo,j3parker/servo,peterjoel/servo,steveklabnik/servo,tschneidereit/servo,jgraham/servo,dagnir/servo,g-k/servo,tafia/servo,pgonda/servo,nnethercote/servo,dagnir/servo,mattnenterprise/servo,youprofit/servo,A-deLuna/servo,huonw/servo,eddyb/servo,CJ8664/servo,fiji-flo/servo,CJ8664/servo,wartman4404/servo,pyecs/servo,jlegendary/servo,jlegendary/servo,jimberlage/servo,wpgallih/servo,rnestler/servo,notriddle/servo,dagnir/servo,paulrouget/servo,notriddle/servo,tafia/servo,KiChjang/servo,emilio/servo,zentner-kyle/servo,emilio/servo,s142857/servo,aidanhs/servo,zhangjunlei26/servo,anthgur/servo,ryancanhelpyou/servo,boghison/servo,wpgallih/servo,dhananjay92/servo,dvberkel/servo,saneyuki/servo,anthgur/servo,g-k/servo,mattnenterprise/servo,pgonda/servo,samfoo/servo,rixrix/servo,splav/servo,boghison/servo,AnthonyBroadCrawford/servo,dhananjay92/servo,pyecs/servo,CJ8664/servo,ConnorGBrewster/servo,meh/servo,caldwell/servo,eddyb/servo,samfoo/servo,KiChjang/servo,thiagopnts/servo,nerith/servo,kindersung/servo,cbrewster/servo,bjwbell/servo,pgonda/servo,avadacatavra/servo,nick-thompson/servo,huonw/servo,cbrewster/servo,nnethercot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