[PM] Re-format this code with clang-format before making substantial

changes to it. No functionality changed.

You may wonder why on earth touching this code is involved in the pass
manager work as indicated by my lovely '[PM]' tag? Let me tell you
a story.

<redacted>

Yea, it's too long of a story. Let us say that there are yaks, many of
them. I am busy shaving them as fast as I can.

llvm-svn: 195715