The combination of [[gsl::Owner]], [[gsl::Pointer]] and
[[clang::lifetimebound]] attributes makes it possible for clang to
detect some basic form of lifetime issues.
Those are expressed in terms of MOZ_GSL_OWNER, MOZ_GSL_POINTER and
MOZ_LIFETIME_BOUND.
Differential Revision: https://phabricator.services.mozilla.com/D241077