perfschema compilation, test and misc fixes

storage/perfschema/rpl_gtid.h

@@ -0,0 +1,17 @@
+#ifndef STORAGE_PERFSCHEMA_RPL_GTID_INCLUDED
+#define STORAGE_PERFSCHEMA_RPL_GTID_INCLUDED
+
+struct TABLE;
+
+#include "../../sql/rpl_gtid.h"
+
+class Gtid_specification: public rpl_gtid
+{
+public:
+  size_t to_string(char *buf)
+  {
+    return my_snprintf(buf, GTID_MAX_STR_LENGTH, "%u-%u-%llu",
+                       domain_id, server_id, seq_no);
+  }
+};
+#endif