Implement LWG#2873: 'Add noexcept to several shared_ptr related functions' This issue missed a couple, so I added those as well (see LWG#2942)

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@299963 91177308-0d34-0410-b5e6-96231b3b80d8
7 files changed