[ThinLTO] Wire up ThinLTO and new PM

Summary: This patch teaches clang to use and propagate new PM in ThinLTO.

Reviewers: davide, chandlerc, tejohnson

Subscribers: mehdi_amini, Prazek, inglorion, cfe-commits

Differential Revision: https://reviews.llvm.org/D33692

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@304496 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed