Fix issue with SCCs getting added to the call graph multiple times.
Fix issue with SCCs getting added to the call graph multiple times.

Don't create the SCC finder for each root - we end up losing the state
of what we've already visited.

Swift SVN r21569

Jnosh/swift,devincoughlin/swift,sdulal/swift,stephentyrone/swift,amraboelela/swift,LeoShimonaka/swift,hooman/swift,modocache/swift,slavapestov/swift,roambotics/swift,parkera/swift,cbrentharris/swift,codestergit/swift,brentdax/swift,kentya6/swift,milseman/swift,deyton/swift,IngmarStein/swift,ben-ng/swift,JGiola/swift,gregomni/swift,IngmarStein/swift,allevato/swift,KrishMunot/swift,practicalswift/swift,MukeshKumarS/Swift,devincoughlin/swift,CodaFi/swift,natecook1000/swift,manavgabhawala/swift,swiftix/swift,ben-ng/swift,shahmishal/swift,tkremenek/swift,jopamer/swift,Jnosh/swift,amraboelela/swift,gribozavr/swift,gottesmm/swift,gottesmm/swift,jmgc/swift,sschiau/swift,kusl/swift,kentya6/swift,nathawes/swift,kstaring/swift,KrishMunot/swift,huonw/swift,allevato/swift,harlanhaskins/swift,sschiau/swift,alblue/swift,danielmartin/swift,amraboelela/swift,frootloops/swift,MukeshKumarS/Swift,hooman/swift,aschwaighofer/swift,ahoppen/swift,parkera/swift,aschwaighofer/swift,parkera/swift,calebd/swift,rudkx/swift,ken0nek/swift,parkera/swift,JGiola/swift,aschwaighofer/swift,karwa/swift,swiftix/swift,natecook1000/swift,gmilos/swift,brentdax/swift,apple/swift,OscarSwanros/swift,allevato/swift,amraboelela/swift,harlanhaskins/swift,mightydeveloper/swift,Ivacker/swift,khizkhiz/swift,frootloops/swift,JaSpa/swift,mightydeveloper/swift,LeoShimonaka/swift,jckarter/swift,milseman/swift,hughbe/swift,shajrawi/swift,deyton/swift,hooman/swift,OscarSwanros/swift,sschiau/swift,jtbandes/swift,cbrentharris/swift,karwa/swift,stephentyrone/swift,xedin/swift,ahoppen/swift,calebd/swift,return/swift,swiftix/swift.old,uasys/swift,MukeshKumarS/Swift,SwiftAndroid/swift,adrfer/swift,danielmartin/swift,danielmartin/swift,emilstahl/swift,bitjammer/swift,arvedviehweger/swift,emilstahl/swift,huonw/swift,brentdax/swift,kusl/swift,ken0nek/swift,adrfer/swift,tinysun212/swift-windows,shajrawi/swift,jopamer/swift,shahmishal/swift,brentdax/swift,zisko/swift,russbishop/swift,devincoughlin/swift,allevato/swift,benlangmuir/swift,LeoShimonaka/swift,IngmarStein/swift,JaSpa/swift,KrishMunot/swift,karwa/swift,xwu/swift,natecook1000/swift,SwiftAndroid/swift,shajrawi/swift,ahoppen/swift,cbrentharris/swift,arvedviehweger/swift,xwu/swift,MukeshKumarS/Swift,sschiau/swift,karwa/swift,LeoShimonaka/swift,djwbrown/swift,kperryua/swift,ben-ng/swift,xwu/swift,roambotics/swift,deyton/swift,lorentey/swift,allevato/swift,shajrawi/swift,harlanhaskins/swift,sdulal/swift,natecook1000/swift,jckarter/swift,austinzheng/swift,SwiftAndroid/swift,LeoShimonaka/swift,arvedviehweger/swift,bitjammer/swift,djwbrown/swift,harlanhaskins/swift,jopamer/swift,Jnosh/swift,gmilos/swift,kstaring/swift,lorentey/swift,hughbe/swift,jmgc/swift,shajrawi/swift,dreamsxin/swift,uasys/swift,jtbandes/swift,zisko/swift,alblue/swift,adrfer/swift,lorentey/swift,glessard/swift,emilstahl/swift,glessard/swift,jtbandes/swift,jopamer/swift,amraboelela/swift,swiftix/swift,danielmartin/swift,swiftix/swift,KrishMunot/swift,ben-ng/swift,jopamer/swift,natecook1000/swift,sdulal/swift,tinysun212/swift-windows,tkremenek/swift,russbishop/swift,nathawes/swift,karwa/swift,rudkx/swift,bitjammer/swift,IngmarStein/swift,parkera/swift,alblue/swift,Jnosh/swift,return/swift,roambotics/swift,ken0nek/swift,therealbnut/swift,tinysun212/swift-windows,harlanhaskins/swift,stephentyrone/swift,therealbnut/swift,therealbnut/swift,arvedviehweger/swift,atrick/swift,benlangmuir/swift,MukeshKumarS/Swift,Jnosh/swift,shajrawi/swift,jckarter/swift,kperryua/swift,airspeedswift/swift,OscarSwanros/swift,practicalswift/swift,dduan/swift,gottesmm/swift,stephentyrone/swift,milseman/swift,huonw/swift,benlangmuir/swift,russbishop/swift,aschwaighofer/swift,kentya6/swift,kusl/swift,return/swift,kperryua/swift,ahoppen/swift,zisko/swift,sschiau/swift,shahmishal/swift,manavgabhawala/swift,gregomni/swift,mightydeveloper/swift,rudkx/swift,xedin/swift,calebd/swift,hughbe/swift,xedin/swift,frootloops/swift,tjw/swift,airspeedswift/swift,sschiau/swift,swiftix/swift.old,swiftix/swift,CodaFi/swift,harlanhaskins/swift,manavgabhawala/swift,djwbrown/swift,parkera/swift,frootloops/swift,deyton/swift,devincoughlin/swift,glessard/swift,OscarSwanros/swift,felix91gr/swift,bitjammer/swift,alblue/swift,ken0nek/swift,rudkx/swift,gribozavr/swift,atrick/swift,codestergit/swift,allevato/swift,shahmishal/swift,xedin/swift,atrick/swift,danielmartin/swift,Ivacker/swift,gottesmm/swift,mightydeveloper/swift,sdulal/swift,JGiola/swift,hooman/swift,johnno1962d/swift,uasys/swift,CodaFi/swift,karwa/swift,ben-ng/swift,lorentey/swift,therealbnut/swift,hughbe/swift,devincoughlin/swift,OscarSwanros/swift,tardieu/swift,deyton/swift,KrishMunot/swift,calebd/swift,tkremenek/swift,djwbrown/swift,swiftix/swift.old,MukeshKumarS/Swift,return/swift,tjw/swift,tardieu/swift,xwu/swift,mightydeveloper/swift,gottesmm/swift,gottesmm/swift,Ivacker/swift,stephentyrone/swift,apple/swift,tinysun212/swift-windows,shahmishal/swift,roambotics/swift,LeoShimonaka/swift,natecook1000/swift,milseman/swift,MukeshKumarS/Swift,Ivacker/swift,kstaring/swift,kusl/swift,dduan/swift,danielmartin/swift,CodaFi/swift,JaSpa/swift,nathawes/swift,amraboelela/swift,apple/swift,brentdax/swift,felix91gr/swift,gregomni/swift,frootloops/swift,felix91gr/swift,stephentyrone/swift,cbrentharris/swift,SwiftAndroid/swift,JaSpa/swift,hooman/swift,djwbrown/swift,nathawes/swift,cbrentharris/swift,JaSpa/swift,hooman/swift,uasys/swift,sdulal/swift,gottesmm/swift,gribozavr/swift,kentya6/swift,xwu/swift,felix91gr/swift,tkremenek/swift,benlangmuir/swift,zisko/swift,kusl/swift,JGiola/swift,khizkhiz/swift,airspeedswift/swift,rudkx/swift,tkremenek/swift,LeoShimonaka/swift,johnno1962d/swift,gribozavr/swift,parkera/swift,harlanhaskins/swift,zisko/swift,shahmishal/swift,practicalswift/swift,KrishMunot/swift,deyton/swift,therealbnut/swift,johnno1962d/swift,codestergit/swift,airspeedswift/swift,dduan/swift,practicalswift/swift,kusl/swift,gregomni/swift,stephentyrone/swift,rudkx/swift,kentya6/swift,airspeedswift/swift,lorentey/swift,aschwaighofer/swift,tardieu/swift,tjw/swift,khizkhiz/swift,jtbandes/swift,tardieu/swift,slavapestov/swift,khizkhiz/swift,jmgc/swift,LeoShimonaka/swift,ben-ng/swift,johnno1962d/swift,austinzheng/swift,atrick/swift,dduan/swift,gregomni/swift,russbishop/swift,JaSpa/swift,Jnosh/swift,amraboelela/swift,johnno1962d/swift,ken0nek/swift,apple/swift,ben-ng/swift,jckarter/swift,shajrawi/swift,practicalswift/swift,swiftix/swift,sdulal/swift,felix91gr/swift,dduan/swift,adrfer/swift,jtbandes/swift,khizkhiz/swift,dduan/swift,CodaFi/swift,gmilos/swift,xedin/swift,practicalswift/swift,frootloops/swift,kperryua/swift,felix91gr/swift,karwa/swift,austinzheng/swift,gmilos/swift,uasys/swift,gribozavr/swift,JGiola/swift,glessard/swift,manavgabhawala/swift,jmgc/swift,kstaring/swift,lorentey/swift,mightydeveloper/swift,uasys/swift,codestergit/swift,jopamer/swift,glessard/swift,huonw/swift,sdulal/swift,bitjammer/swift,allevato/swift,kperryua/swift,milseman/swift,kstaring/swift,shahmishal/swift,tkremenek/swift,jtbandes/swift,calebd/swift,Ivacker/swift,kentya6/swift,CodaFi/swift,xedin/swift,frootloops/swift,swiftix/swift.old,emilstahl/swift,devincoughlin/swift,IngmarStein/swift,return/swift,OscarSwanros/swift,JaSpa/swift,jckarter/swift,emilstahl/swift,tinysun212/swift-windows,modocache/swift,jckarter/swift,sdulal/swift,KrishMunot/swift,manavgabhawala/swift,ken0nek/swift,aschwaighofer/swift,swiftix/swift.old,gribozavr/swift,huonw/swift,roambotics/swift,alblue/swift,therealbnut/swift,bitjammer/swift,slavapestov/swift,gribozavr/swift,emilstahl/swift,bitjammer/swift,slavapestov/swift,adrfer/swift,deyton/swift,ahoppen/swift,tardieu/swift,roambotics/swift,tardieu/swift,sschiau/swift,benlangmuir/swift,tkremenek/swift,huonw/swift,johnno1962d/swift,modocache/swift,tjw/swift,natecook1000/swift,kentya6/swift,kstaring/swift,tinysun212/swift-windows,benlangmuir/swift,SwiftAndroid/swift,kstaring/swift,arvedviehweger/swift,zisko/swift,xedin/swift,tardieu/swift,slavapestov/swift,airspeedswift/swift,kentya6/swift,apple/swift,practicalswift/swift,alblue/swift,tjw/swift,manavgabhawala/swift,devincoughlin/swift,uasys/swift,khizkhiz/swift,modocache/swift,austinzheng/swift,tjw/swift,russbishop/swift,atrick/swift,brentdax/swift,cbrentharris/swift,jmgc/swift,huonw/swift,xwu/swift,swiftix/swift,dreamsxin/swift,ahoppen/swift,OscarSwanros/swift,milseman/swift,brentdax/swift,IngmarStein/swift,cbrentharris/swift,cbrentharris/swift,khizkhiz/swift,modocache/swift,xedin/swift,hooman/swift,apple/swift,modocache/swift,austinzheng/swift,calebd/swift,Jnosh/swift,karwa/swift,danielmartin/swift,calebd/swift,hughbe/swift,kperryua/swift,swiftix/swift.old,gmilos/swift,parkera/swift,arvedviehweger/swift,nathawes/swift,emilstahl/swift,milseman/swift,shajrawi/swift,aschwaighofer/swift,modocache/swift,mightydeveloper/swift,nathawes/swift,gregomni/swift,IngmarStein/swift,manavgabhawala/swift,adrfer/swift,alblue/swift,johnno1962d/swift,xwu/swift,russbishop/swift,kusl/swift,nathawes/swift,jopamer/swift,SwiftAndroid/swift,adrfer/swift,tinysun212/swift-windows,zisko/swift,shahmishal/swift,gmilos/swift,atrick/swift,Ivacker/swift,swiftix/swift.old,Ivacker/swift,airspeedswift/swift,gmilos/swift,ken0nek/swift,CodaFi/swift,sschiau/swift,return/swift,kperryua/swift,felix91gr/swift,JGiola/swift,hughbe/swift,dduan/swift,slavapestov/swift,devincoughlin/swift,lorentey/swift,arvedviehweger/swift,jckarter/swift,lorentey/swift,austinzheng/swift,codestergit/swift,Ivacker/swift,therealbnut/swift,jtbandes/swift,djwbrown/swift,SwiftAndroid/swift,codestergit/swift,russbishop/swift,djwbrown/swift,practicalswift/swift,jmgc/swift,jmgc/swift,return/swift,swiftix/swift.old,mightydeveloper/swift,austinzheng/swift,slavapestov/swift,glessard/swift,gribozavr/swift,hughbe/swift,emilstahl/swift,tjw/swift,kusl/swift,codestergit/swift