Parser: don't set 'Invalid' bit on SubscriptDecls too eagerly.
Parser: don't set 'Invalid' bit on SubscriptDecls too eagerly.

This makes the typechecker skip the decl completely, and it does not set types
on parameter patterns (not even to ErrorType).  In fact, in the problematic
case the type checker can cope with the decl just fine, so don't set the
Invalid bit.

This fixes a crash in code completion when it encounters such a decl,
rdar://16132349


Swift SVN r14459

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