clang-modernize: Reset LoopConvert's TU tracking info per TU

The LoopConvert transform makes use of data structures it builds up over
the course of transforming a TU. Until now, these data structures
weren't being cleared out before the next TU was being processed.

Fixes PR17253.

Differential Revision: http://llvm-reviews.chandlerc.com/D175



git-svn-id: https://llvm.org/svn/llvm-project/clang-tools-extra/trunk@191448 91177308-0d34-0410-b5e6-96231b3b80d8
clang-modernize: Fixing a few left over cpp11-migrate references

Build files for unit tests hadn't been updated yet.



git-svn-id: https://llvm.org/svn/llvm-project/clang-tools-extra/trunk@191451 91177308-0d34-0410-b5e6-96231b3b80d8