Change the default for supporting ObjC GC to true.  This shouldn't really be in ToolChain at all, since it's a property of the objc runtime library.
Change the default for supporting ObjC GC to true.  This shouldn't really be in ToolChain at all, since it's a property of the objc runtime library.



git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@131856 91177308-0d34-0410-b5e6-96231b3b80d8

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