MSVC 2013 type trait support

Implement type trait primitives used in the latest edition of the Microsoft
standard C++ library type_traits header.

With this change we can parse much of the Visual Studio 2013 standard headers,
particularly anything that includes <type_traits>.

Fully implemented, available in all language modes:

 * __is_constructible()
 * __is_nothrow_constructible()
 * __is_nothrow_assignable()

Partially implemented, semantic analysis WIP, available as MS extensions:

 * __is_destructible()
 * __is_nothrow_destructible()

llvm-svn: 199619
diff --git a/clang/test/CXX/except/except.spec/canonical.cpp b/clang/test/CXX/except/except.spec/canonical.cpp
index b6d3e9c..d6dc258 100644
--- a/clang/test/CXX/except/except.spec/canonical.cpp
+++ b/clang/test/CXX/except/except.spec/canonical.cpp
@@ -9,7 +9,7 @@
 template <class _Tp> _Tp&& declval() noexcept;
 
 template <class _Tp, class... _Args>
-struct __is_nothrow_constructible
+struct _is_nothrow_constructible
 {
   static const bool value = noexcept(_Tp(declval<_Args>()...));
 };
@@ -22,7 +22,7 @@
   typedef _Allocator allocator_type;
 
   basic_string()
-      noexcept(__is_nothrow_constructible<allocator_type>::value);
+      noexcept(_is_nothrow_constructible<allocator_type>::value);
 };
 
 template <class, class, class _Compare>
@@ -30,7 +30,7 @@
 {
 public:
   __map_value_compare()
-      noexcept(__is_nothrow_constructible<_Compare>::value);
+      noexcept(_is_nothrow_constructible<_Compare>::value);
 };
 
 struct less
@@ -45,10 +45,10 @@
 
 
 template<class T, class _Traits, class _Allocator>
-basic_string<T, _Traits, _Allocator>::basic_string() noexcept(__is_nothrow_constructible<allocator_type>::value) {}
+basic_string<T, _Traits, _Allocator>::basic_string() noexcept(_is_nothrow_constructible<allocator_type>::value) {}
 
 template <class T, class Value, class _Compare>
 __map_value_compare<T, Value, _Compare>::__map_value_compare()
-  noexcept(__is_nothrow_constructible<_Compare>::value) {}
+  noexcept(_is_nothrow_constructible<_Compare>::value) {}
 
 }  // std