Refine noreturn handling.  Fixes -Wmissing-noreturn so that it doesn't
complain that functions that have a return statement should be
declared noreturn.  Fixed PR5286.

llvm-svn: 85195
diff --git a/clang/lib/Sema/Sema.h b/clang/lib/Sema/Sema.h
index fa10dea..f108878 100644
--- a/clang/lib/Sema/Sema.h
+++ b/clang/lib/Sema/Sema.h
@@ -988,7 +988,7 @@
   void CheckCXXDefaultArguments(FunctionDecl *FD);
   void CheckExtraCXXDefaultArguments(Declarator &D);
   enum ControlFlowKind { NeverFallThrough = 0, MaybeFallThrough = 1,
-                         AlwaysFallThrough = 2 };
+                         AlwaysFallThrough = 2, NeverFallThroughOrReturn = 3 };
   ControlFlowKind CheckFallThrough(Stmt *);
 
   Scope *getNonFieldDeclScope(Scope *S);