Auto merge of #7143 - larsbergstrom:user_agent, r=mbrubeck
Auto merge of #7143 - larsbergstrom:user_agent, r=mbrubeck

Add the Servo User Agent strings

Fixes #4331. I've tested this out on desktop and Android on "the usual" sites (reddit, cnn, github, wikipedia, etc.).

r? @mbrubeck @metajack

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dsandeephegde/servo,avadacatavra/servo,saratang/servo,mattnenterprise/servo,GyrosOfWar/servo,jdramani/servo,cbrewster/servo,aidanhs/servo,CJ8664/servo,sadmansk/servo,saneyuki/servo,larsbergstrom/servo,SimonSapin/servo,youprofit/servo,brendandahl/servo,upsuper/servo,tafia/servo,szeged/servo,walac/servo,pyfisch/servo,szeged/servo,dvberkel/servo,dagnir/servo,nnethercote/servo,rentongzhang/servo,DominoTree/servo,saratang/servo,sadmansk/servo,kindersung/servo,tafia/servo,KiChjang/servo,caldwell/servo,rentongzhang/servo,peterjoel/servo,CJ8664/servo,mbrubeck/servo,GyrosOfWar/servo,fiji-flo/servo,sadmansk/servo,DominoTree/servo,WriterOfAlicrow/servo,upsuper/servo,caldwell/servo,dsandeephegde/servo,brendandahl/servo,brendandahl/servo,dhananjay92/servo,szeged/servo,canaltinova/servo,dhananjay92/servo,DominoTree/servo,jimberlage/servo,AnthonyBroadCrawford/servo,notriddle/servo,anthgur/servo,saratang/servo,emilio/servo,avadacatavra/servo,mdibaiee/servo,dati91/servo,mbrubeck/servo,brendandahl/servo,SimonSapin/servo,A-deLuna/servo,GyrosOfWar/servo,steveklabnik/servo,youprofit/servo,dhananjay92/servo,notriddle/servo,larsbergstrom/servo,dagnir/servo,dhananjay92/servo,splav/servo,notriddle/servo,steveklabnik/servo,mdibaiee/servo,walac/servo,pyfisch/servo,anthgur/servo,codemac/servo,A-deLuna/servo,mattnenterprise/servo,A-deLuna/servo,caldwell/servo,aidanhs/servo,splav/servo,mdibaiee/servo,pyfisch/servo,CJ8664/servo,eddyb/servo,peterjoel/servo,huonw/servo,nrc/servo,avadacatavra/servo,mattnenterprise/servo,saneyuki/servo,dsandeephegde/servo,RenaudParis/servo,youprofit/servo,ConnorGBrewster/servo,youprofit/servo,pyfisch/servo,upsuper/servo,sadmansk/servo,dvberkel/servo,steveklabnik/servo,fiji-flo/servo,mattnenterprise/servo,saneyuki/servo,canaltinova/servo,canaltinova/servo,RenaudParis/servo,vks/servo,szeged/servo,akosel/servo,jdramani/servo,peterjoel/servo,DominoTree/servo,dagnir/servo,dsandeephegde/servo,meh/servo,saratang/servo,SimonSapin/servo,jdramani/servo,rnestler/servo,ConnorGBrewster/servo,caldwell/servo,jdramani/servo,peterjoel/servo,nnethercote/servo,walac/servo,fiji-flo/servo,RenaudParis/servo,thiagopnts/servo,brendandahl/servo,bjwbell/servo,kindersung/servo,j3parker/servo,dagnir/servo,caldwell/servo,szeged/servo,aidanhs/servo,AnthonyBroadCrawford/servo,splav/servo,jlegendary/servo,A-deLuna/servo,fiji-flo/servo,ConnorGBrewster/servo,CJ8664/servo,rnestler/servo,mattnenterprise/servo,KiChjang/servo,szeged/servo,SimonSapin/servo,notriddle/servo,larsbergstrom/servo,jlegendary/servo,KiChjang/servo,larsbergstrom/servo,mdibaiee/servo,RenaudParis/servo,larsbergstrom/servo,pyfisch/servo,rnestler/servo,zentner-kyle/servo,canaltinova/servo,peterjoel/servo,runarberg/servo,SimonSapin/servo,DominoTree/servo,paulrouget/servo,dvberkel/servo,DominoTree/servo,emilio/servo,jlegendary/servo,RenaudParis/servo,notriddle/servo,DominoTree/servo,dati91/servo,CJ8664/servo,WriterOfAlicrow/servo,eddyb/servo,wartman4404/servo,fiji-flo/servo,avadacatavra/servo,KiChjang/servo,AnthonyBroadCrawford/servo,mbrubeck/servo,KiChjang/servo,j3parker/servo,WriterOfAlicrow/servo,dhananjay92/servo,mdibaiee/servo,j3parker/servo,avadacatavra/servo,mbrubeck/servo,mattnenterprise/servo,akosel/servo,avadacatavra/servo,kindersung/servo,codemac/servo,runarberg/servo,cbrewster/servo,thiagopnts/servo,jimberlage/servo,CJ8664/servo,pyfisch/servo,kindersung/servo,GyrosOfWar/servo,paulrouget/servo,notriddle/servo,paulrouget/servo,akosel/servo,zentner-kyle/servo,mdibaiee/servo,caldwell/servo,eddyb/servo,rnestler/servo,huonw/servo,saneyuki/servo,avadacatavra/servo,dvberkel/servo,paulrouget/servo,anthgur/servo,GyrosOfWar/servo,A-deLuna/servo,RenaudParis/servo,mattnenterprise/servo,aidanhs/servo,ConnorGBrewster/servo,bjwbell/servo,aidanhs/servo,canaltinova/servo,sadmansk/servo,CJ8664/servo,dhananjay92/servo,jlegendary/servo,rentongzhang/servo,tafia/servo,aidanhs/servo,notriddle/servo,nrc/servo,anthgur/servo,upsuper/servo,zentner-kyle/servo,jimberlage/servo,runarberg/servo,wartman4404/servo,huonw/servo,paulrouget/servo,zentner-kyle/servo,rentongzhang/servo,anthgur/servo,DominoTree/servo,cbrewster/servo,saneyuki/servo,ConnorGBrewster/servo,A-deLuna/servo,jimberlage/servo,meh/servo,A-deLuna/servo,splav/servo,splav/servo,jdramani/servo,anthgur/servo,jimberlage/servo,j3parker/servo,steveklabnik/servo,GyrosOfWar/servo,peterjoel/servo,fiji-flo/servo,nrc/servo,jdramani/servo,emilio/servo,RenaudParis/servo,notriddle/servo,splav/servo,vks/servo,dvberkel/servo,cbrewster/servo,nnethercote/servo,KiChjang/servo,dsandeephegde/servo,dagnir/servo,paulrouget/servo,ConnorGBrewster/servo,dvberkel/servo,rentongzhang/servo,eddyb/servo,walac/servo,saneyuki/servo,youprofit/servo,dati91/servo,saratang/servo,dati91/servo,jimberlage/servo,brendandahl/servo,larsbergstrom/servo,upsuper/servo,dvberkel/servo,zentner-kyle/servo,akosel/servo,dati91/servo,nnethercote/servo,thiagopnts/servo,meh/servo,ConnorGBrewster/servo,tafia/servo,larsbergstrom/servo,rentongzhang/servo,AnthonyBroadCrawford/servo,jlegendary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