Replace __cplusplus comparisons and dialect __has_feature checks with TEST_STD_VER.

This is a huge cleanup that helps make the libc++ test suite more portable.
Patch from STL@microsoft.com. Thanks STL!


git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@272716 91177308-0d34-0410-b5e6-96231b3b80d8

test/std/strings/basic.string/string.ops/string_compare/pointer.pass.cpp

@@ -53,7 +53,7 @@ int main()
     test(S("abcdefghijklmnopqrst"), "abcdefghij", 10);
     test(S("abcdefghijklmnopqrst"), "abcdefghijklmnopqrst", 0);
     }
-#if __cplusplus >= 201103L
+#if TEST_STD_VER >= 11
     {
     typedef std::basic_string<char, std::char_traits<char>, min_allocator<char>> S;
     test(S(""), "", 0);

test/std/strings/basic.string/string.ops/string_compare/size_size_pointer.pass.cpp

@@ -362,7 +362,7 @@ int main()
     test1<S>();
     test2<S>();
     }
-#if __cplusplus >= 201103L
+#if TEST_STD_VER >= 11
     {
     typedef std::basic_string<char, std::char_traits<char>, min_allocator<char>> S;
     test0<S>();

test/std/strings/basic.string/string.ops/string_compare/size_size_pointer_size.pass.cpp

@@ -1304,7 +1304,7 @@ int main()
     test10<S>();
     test11<S>();
     }
-#if __cplusplus >= 201103L
+#if TEST_STD_VER >= 11
     {
     typedef std::basic_string<char, std::char_traits<char>, min_allocator<char>> S;
     test0<S>();

test/std/strings/basic.string/string.ops/string_compare/size_size_string.pass.cpp

@@ -362,7 +362,7 @@ int main()
     test1<S>();
     test2<S>();
     }
-#if __cplusplus >= 201103L
+#if TEST_STD_VER >= 11
     {
     typedef std::basic_string<char, std::char_traits<char>, min_allocator<char>> S;
     test0<S>();

test/std/strings/basic.string/string.ops/string_compare/size_size_string_size_size.pass.cpp

@@ -5885,7 +5885,7 @@ int main()
     test54<S>();
     test55<S>();
     }
-#if __cplusplus >= 201103L
+#if TEST_STD_VER >= 11
     {
     typedef std::basic_string<char, std::char_traits<char>, min_allocator<char>> S;
     test0<S>();

test/std/strings/basic.string/string.ops/string_compare/string.pass.cpp

@@ -53,7 +53,7 @@ int main()
     test(S("abcdefghijklmnopqrst"), S("abcdefghij"), 10);
     test(S("abcdefghijklmnopqrst"), S("abcdefghijklmnopqrst"), 0);
     }
-#if __cplusplus >= 201103L
+#if TEST_STD_VER >= 11
     {
     typedef std::basic_string<char, std::char_traits<char>, min_allocator<char>> S;
     test(S(""), S(""), 0);