Initial implementation of CharUnits, an opaque value class for representing sizes, offsets, and alignments in character units.
Initial implementation of CharUnits, an opaque value class for representing
sizes, offsets, and alignments in character units.


git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@91683 91177308-0d34-0410-b5e6-96231b3b80d8

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