Simplify some code and make it easier to understand.
Simplify some code and make it easier to understand.

CSE some stripUpCasts() calls and do a little renaming to aid in
understandability. NFC.

Swift SVN r25941

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