[PATCH] [libcxx] Remove use of default function template parameters in type traits. Fixes DR20484

[Agustín Bergé]

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Comment at: include/type_traits:1554
@@ +1553,3 @@
+	static char  __test (
+        typename __is_destructible_apply<decltype(_VSTD::declval<_Tp1&>().~_Tp1())>::type
+    );
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Isn't the `decltype` still a problem if it has to compile in C++03 mode?

http://reviews.llvm.org/D4735