Revert "cpp11-migrate: Add a class to support include directives modifications"

This reverts commit r189017.

It broke the windows bots:
- http://bb.pgr.jp/builders/ninja-clang-i686-msc17-R/builds/4176
- http://bb.pgr.jp/builders/cmake-clang-i686-mingw32/builds/3837

llvm-svn: 189037