Implement full support for non-pointer pointers in custom allocators for string. This completes the custom pointer support for the entire library.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@185167 91177308-0d34-0410-b5e6-96231b3b80d8

test/strings/basic.string/string.capacity/clear.pass.cpp

@@ -14,6 +14,8 @@
 #include <string>
 #include <cassert>
 
+#include "../min_allocator.h"
+
 template <class S>
 void
 test(S s)
@@ -24,6 +26,7 @@ test(S s)
 
 int main()
 {
+    {
     typedef std::string S;
     S s;
     test(s);
@@ -35,4 +38,20 @@ int main()
     s.assign(100, 'a');
     s.erase(50);
     test(s);
+    }
+#if __cplusplus >= 201103L
+    {
+    typedef std::basic_string<char, std::char_traits<char>, min_allocator<char>> S;
+    S s;
+    test(s);
+
+    s.assign(10, 'a');
+    s.erase(5);
+    test(s);
+
+    s.assign(100, 'a');
+    s.erase(50);
+    test(s);
+    }
+#endif
 }