UninitializedValues: introduce ValueVector:reference class to forward to llvm::BitVector.  No real functionality change, but this is a stepping stone to moving to tri-state logic.
UninitializedValues: introduce ValueVector:reference class to forward to llvm::BitVector.  No real functionality change, but this is a stepping stone to moving to tri-state logic.

git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@127665 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang,apple/swift-clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,apple/swift-clang