[clang] [clang-tools-extra] [clang] Detect pointee mutations in placement new expressions (PR #187508)

[Victor Chernyakin via cfe-commits]

localspook wrote:

@carlosgalvezp FYI, since your review is still marked “requested changes”, this PR can’t be merged

https://github.com/llvm/llvm-project/pull/187508