[libc++] Move all the remaining .fail.cpp tests to .verify.cpp

I made sure they all had some expected-error output in them. Many of
these tests would be better implemented as a positive test using SFINAE,
but this is beyond the scope of this patch.

Differential Revision: https://reviews.llvm.org/D153980

libcxx/test/std/utilities/intseq/intseq.make/make_integer_seq.verify.cpp

@@ -17,22 +17,15 @@
 // UNSUPPORTED: stdlib=libstdc++
 
 #include <utility>
-#include <type_traits>
-#include <cassert>
 
 #include "test_macros.h"
 
-int main(int, char**)
-{
-  typedef std::make_integer_sequence<int, -3> MakeSeqT;
+typedef std::make_integer_sequence<int, -3> MakeSeqT;
 
-  // std::make_integer_sequence is implemented using a compiler builtin if available.
-  // this builtin has different diagnostic messages than the fallback implementation.
-#if TEST_HAS_BUILTIN(__make_integer_seq) && !defined(_LIBCPP_TESTING_FALLBACK_MAKE_INTEGER_SEQUENCE)
-  MakeSeqT i; // expected-error@*:* {{integer sequences must have non-negative sequence length}}
+// std::make_integer_sequence is implemented using a compiler builtin if available.
+// this builtin has different diagnostic messages than the fallback implementation.
+#if TEST_HAS_BUILTIN(__make_integer_seq)
+MakeSeqT i; // expected-error@*:* {{integer sequences must have non-negative sequence length}}
 #else
-  MakeSeqT i; // expected-error-re@*:* {{{{(static_assert|static assertion)}} failed{{.*}}std::make_integer_sequence must have a non-negative sequence length}}
+MakeSeqT i; // expected-error-re@*:* {{{{(static_assert|static assertion)}} failed{{.*}}std::make_integer_sequence must have a non-negative sequence length}}
 #endif
-
-  return 0;
-}

libcxx/test/std/utilities/intseq/intseq.make/make_integer_seq_fallback.verify.cpp

@@ -16,5 +16,9 @@
 // This test hangs during recursive template instantiation with libstdc++
 // UNSUPPORTED: stdlib=libstdc++
 
-#define _LIBCPP_TESTING_FALLBACK_MAKE_INTEGER_SEQUENCE
-#include "make_integer_seq.fail.cpp"
+// ADDITIONAL_COMPILE_FLAGS: -D_LIBCPP_TESTING_FALLBACK_MAKE_INTEGER_SEQUENCE
+
+#include <utility>
+
+typedef std::make_integer_sequence<int, -3> MakeSeqT;
+MakeSeqT i; // expected-error-re@*:* {{{{(static_assert|static assertion)}} failed{{.*}}std::make_integer_sequence must have a non-negative sequence length}}