MFC r254582:

MFC r254582:

Pull in r182983 from upstream clang trunk:

  Fix handling of braced-init-list as reference initializer within
  aggregate initialization. Previously we would incorrectly require an
  extra set of braces around such initializers.

Pull in r188718 from upstream clang trunk:

  Handle init lists and _Atomic fields.

  Fixes PR16931.

These fixes are needed for the atomic_flag type to work correctly in our
stdatomic.h.

Requested by:	theraven

git-svn-id: svn://svn.freebsd.org/base/stable/9@254728 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f