objective-C: synthesize properties in order of their
declarations to synthesize their ivars in similar
determinstic order so they are laid out in
a determinstic order. // rdar://13192366


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175214 91177308-0d34-0410-b5e6-96231b3b80d8