libstdc++: testsuite/util adjustments for import std

In my import std testing patch, to work around c++/99000 (include after
import) I move #includes of the util/ headers above the import.  And so I
made some adjustments to those headers to support this: adding some missing
dependencies, making sure that in headers that include both importable and
non-importable headers, at least one importable header comes first to work
with my patch to translate e.g. #include <vector> to import <bits/stdc++.h>.

The testsuite_iterators.h avoids a failure in
20_util/specialized_algorithms/uninitialized_copy/constrained.cc from
including <memory> after this header, with a mysterious "no match for
operator<" between long and difference_type.

libstdc++-v3/ChangeLog:

	* testsuite/util/testsuite_allocator.h: Move importable headers up.
	* testsuite/util/testsuite_common_types.h: Likewise.
	* testsuite/util/testsuite_containers.h: Likewise.
	* testsuite/util/testsuite_error.h: Move includes inside
	include guard.
	* testsuite/util/testsuite_greedy_ops.h: #include <cstddef>.
	* testsuite/util/testsuite_iterators.h: #include <utility>.
	* testsuite/util/testsuite_new_operators.h: #include <cstdlib>.
	* testsuite/util/testsuite_random.h: #include <random>.

libstdc++-v3/testsuite/util/testsuite_allocator.h

@@ -26,14 +26,14 @@
 #ifndef _GLIBCXX_TESTSUITE_ALLOCATOR_H
 #define _GLIBCXX_TESTSUITE_ALLOCATOR_H
 
-#include <bits/move.h>
-#include <ext/pointer.h>
-#include <ext/alloc_traits.h>
-#include <testsuite_hooks.h>
 #if __cplusplus >= 201703L
 # include <memory_resource>
 # include <new>
 #endif
+#include <bits/move.h>
+#include <ext/pointer.h>
+#include <ext/alloc_traits.h>
+#include <testsuite_hooks.h>
 
 #if __cplusplus >= 201103L
 # include <unordered_map>

libstdc++-v3/testsuite/util/testsuite_common_types.h

@@ -22,14 +22,6 @@
 #ifndef _TESTSUITE_COMMON_TYPES_H
 #define _TESTSUITE_COMMON_TYPES_H 1
 
-#include <ext/typelist.h>
-
-#include <ext/new_allocator.h>
-#include <ext/malloc_allocator.h>
-#include <ext/mt_allocator.h>
-#include <ext/bitmap_allocator.h>
-#include <ext/pool_allocator.h>
-
 #include <algorithm>
 
 #include <vector>
@@ -53,6 +45,14 @@ namespace unord = std;
 namespace unord = std::tr1;
 #endif
 
+#include <ext/typelist.h>
+
+#include <ext/new_allocator.h>
+#include <ext/malloc_allocator.h>
+#include <ext/mt_allocator.h>
+#include <ext/bitmap_allocator.h>
+#include <ext/pool_allocator.h>
+
 namespace __gnu_test
 {
   using __gnu_cxx::typelist::null_type;

libstdc++-v3/testsuite/util/testsuite_containers.h

@@ -20,10 +20,10 @@
 #ifndef _GLIBCXX_TESTSUITE_CONTAINERS_H
 #define _GLIBCXX_TESTSUITE_CONTAINERS_H
 
-#include <bits/boost_concept_check.h>
 #include <cassert>
-#include <testsuite_container_traits.h>
 #include <utility> // for rel_ops.
+#include <bits/boost_concept_check.h>
+#include <testsuite_container_traits.h>
 
 // Container requirement testing.
 namespace __gnu_test

libstdc++-v3/testsuite/util/testsuite_error.h

@@ -19,12 +19,13 @@
 // <http://www.gnu.org/licenses/>.
 //
 
-#include <string>
-#include <testsuite_hooks.h>
-
 #ifndef _TESTSUITE_ERROR_H
 #define _TESTSUITE_ERROR_H 1
 
+#include <string>
+#include <system_error>
+#include <testsuite_hooks.h>
+
 namespace __gnu_test
 {
   struct test_category : public std::error_category

libstdc++-v3/testsuite/util/testsuite_greedy_ops.h

@@ -15,6 +15,8 @@
 // with this library; see the file COPYING3.  If not see
 // <http://www.gnu.org/licenses/>.
 
+#include <cstddef>
+
 namespace greedy_ops
 {
   struct X

libstdc++-v3/testsuite/util/testsuite_iterators.h

@@ -31,7 +31,7 @@
 #include <bits/stl_iterator_base_types.h>
 
 #if __cplusplus >= 201103L
-#include <bits/move.h>
+#include <utility>
 #endif
 
 #if __cplusplus > 201703L

libstdc++-v3/testsuite/util/testsuite_new_operators.h

@@ -23,6 +23,7 @@
 #define _GLIBCXX_TESTSUITE_NEW_OPERATORS_H
 
 #include <new>
+#include <cstdlib>
 #include <testsuite_hooks.h>
 
 namespace __gnu_test

libstdc++-v3/testsuite/util/testsuite_random.h

@@ -27,6 +27,7 @@
 #include <cmath>
 #include <initializer_list>
 #include <system_error>
+#include <random>
 #include <testsuite_hooks.h>
 
 namespace __gnu_test