WL#7315 Optimizer cost model: main memory management of cost constants

 Follow-up patch: Fix compile failure in unit tests when compiling without performance schema. The fix is to remove the PSI_mutex_key object from being included in the unit tests. This is no longer needed since the unit test no longer needs to link in ha_resolve_by_name().

Author: Olav Sandstaa

unittest/gunit/test_utils.cc

@@ -22,12 +22,6 @@
 #include "mysqld_thd_manager.h" // Global_THD_manager
 #include "opt_costconstantcache.h" // optimizer cost constant cache
 
-/*
- These are needed in order to call ha_resolve_by_name().
-*/
-extern mysql_mutex_t LOCK_plugin;
-static PSI_mutex_key key_LOCK_plugin;
-
 namespace my_testing {
 
 int chars_2_decimal(const char *chars, my_decimal *to)
@@ -64,7 +58,6 @@ void setup_server_for_unit_tests()
  // Initialize Query_logger last, to avoid spurious warnings to stderr.
  query_logger.init();
  init_optimizer_cost_module();
- mysql_mutex_init(key_LOCK_plugin, &LOCK_plugin, MY_MUTEX_INIT_FAST);
 }
 
 void teardown_server_for_unit_tests()
@@ -76,7 +69,6 @@ void teardown_server_for_unit_tests()
  mysql_mutex_destroy(&LOCK_error_log);
  query_logger.cleanup();
  delete_optimizer_cost_module();
- mysql_mutex_destroy(&LOCK_plugin);
 }
 
 void Server_initializer::set_expected_error(uint val)