Fix regression in -Wreturn-type caused by not
handling all CFGElement kinds.  While writing
the test case, it turned out that return-noreturn.cpp
wasn't actually testing anything since it has the wrong -W
flag.  That uncovered another regression with
the handling of destructors marked noreturn.  WIP.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@124238 91177308-0d34-0410-b5e6-96231b3b80d8
3 files changed