auto merge of #5257 : michaelwu/servo/enable-b2s-pie, r=Manishearth
auto merge of #5257 : michaelwu/servo/enable-b2s-pie, r=Manishearth

PIE is required on lollipop. PIE has been supported since jellybean.

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