[D156032] Implement CWG2137 (list-initialization from objects of the same type)

[ldionne]

This issue tracks picking up https://reviews.llvm.org/D156032 from the Phabricator archive, or dropping it in case it has already landed. I want to make sure nothing gets lost.

[llvmbot]

@llvm/issue-subscribers-clang-frontend

Author: Louis Dionne (ldionne)

This issue tracks picking up https://reviews.llvm.org/D156032 from the Phabricator archive, or dropping it in case it has already landed. I want to make sure nothing gets lost.

[cor3ntin]

@MitalAshok Are you still working on that? If so could you create a PR on Github? (Phabricator fell over)
Thanks a lot