[Sema] Do not emit warning about conditional cast bridge when from type is optional
[Sema] Do not emit warning about conditional cast bridge when from type is optional

atrick/swift,benlangmuir/swift,roambotics/swift,roambotics/swift,JGiola/swift,ahoppen/swift,JGiola/swift,gregomni/swift,gregomni/swift,xwu/swift,glessard/swift,JGiola/swift,rudkx/swift,JGiola/swift,atrick/swift,benlangmuir/swift,ahoppen/swift,ahoppen/swift,glessard/swift,apple/swift,apple/swift,apple/swift,gregomni/swift,rudkx/swift,benlangmuir/swift,rudkx/swift,benlangmuir/swift,xwu/swift,ahoppen/swift,xwu/swift,gregomni/swift,apple/swift,atrick/swift,apple/swift,roambotics/swift,ahoppen/swift,rudkx/swift,JGiola/swift,gregomni/swift,JGiola/swift,xwu/swift,atrick/swift,roambotics/swift,xwu/swift,atrick/swift,apple/swift,glessard/swift,gregomni/swift,glessard/swift,rudkx/swift,xwu/swift,roambotics/swift,glessard/swift,roambotics/swift,xwu/swift,glessard/swift,rudkx/swift,ahoppen/swift,atrick/swift,benlangmuir/swift,benlangmuir/swift