[clang] [libcxx] [lldb] [clang]: implement std::meta::is_type (PR #211653)

[Nhat Nguyen via cfe-commits]

changkhothuychung wrote:

The actual change for this PR should be in the second commit, the first commit is from [this PR](https://github.com/llvm/llvm-project/pull/190356)

https://github.com/llvm/llvm-project/pull/211653