Fully reverting r203236 -- it seems the only bots that are happy are the MSVC bots.

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@203237 91177308-0d34-0410-b5e6-96231b3b80d8
[C++11] Updating getUsingDirectives to use iterator_range instead of a std::pair.

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@203239 91177308-0d34-0410-b5e6-96231b3b80d8