[Analysis] Change several Analysis pieces to use NodeRef. NFC.

Reviewers: dblaikie, grosser

Subscribers: mzolotukhin, llvm-commits

Differential Revision: https://reviews.llvm.org/D23625

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@279156 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed