Revert rL359519 : [MemorySSA] Invalidate MemorySSA if AA or DT are invalidated.

Summary:
MemorySSA keeps internal pointers of AA and DT.
If these get invalidated, so should MemorySSA.

Reviewers: george.burgess.iv, chandlerc

Subscribers: jlebar, Prazek, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D61043
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This was causing windows build bot failures

llvm-svn: 359555