Silence dubious warnings in stdlib build.
Silence dubious warnings in stdlib build.

This commit works around warnings about potentially unexpected inferred
types, which in this instance seem less than totally
helpful (rdar://problem/20075313).

Swift SVN r25805

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