noexcept for <list>.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@132562 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/deque b/include/deque
index 6ada42a..10f78a9 100644
--- a/include/deque
+++ b/include/deque
@@ -143,7 +143,8 @@
 
 // specialized algorithms:
 template <class T, class Allocator>
-    void swap(deque<T,Allocator>& x, deque<T,Allocator>& y) noexcept(x.swap(y));
+    void swap(deque<T,Allocator>& x, deque<T,Allocator>& y)
+         noexcept(noexcept(x.swap(y)));
 
 }  // std