Make directory iterator sentinels free.

This trades some complexity in operator== for not introducing static objects
into any functions using recursive directory iterators.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188081 91177308-0d34-0410-b5e6-96231b3b80d8
DebugInfo: provide the ability to add members to a class after it has been constructed

This is necessary to allow Clang to only emit implicit members when
there is code generated for them, rather than whenever they are ODR
used.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188082 91177308-0d34-0410-b5e6-96231b3b80d8
CHECK-LABEL-ify tests


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188087 91177308-0d34-0410-b5e6-96231b3b80d8