optimization: use hton->drop_table in few simple cases

sql/log.cc

@@ -1692,6 +1692,7 @@ int binlog_init(void *p)
                                      binlog_savepoint_rollback_can_release_mdl;
   binlog_hton->commit= binlog_commit;
   binlog_hton->rollback= binlog_rollback;
+  binlog_hton->drop_table= [](handlerton *, const char*) { return 0; };
   if (WSREP_ON || opt_bin_log)
   {
     binlog_hton->prepare= binlog_prepare;

storage/blackhole/ha_blackhole.cc

@@ -399,6 +399,7 @@ static int blackhole_init(void *p)
   blackhole_hton= (handlerton *)p;
   blackhole_hton->db_type= DB_TYPE_BLACKHOLE_DB;
   blackhole_hton->create= blackhole_create_handler;
+  blackhole_hton->drop_table= [](handlerton *, const char*) { return 0; };
   blackhole_hton->flags= HTON_CAN_RECREATE | HTON_AUTOMATIC_DELETE_TABLE;
 
   mysql_mutex_init(bh_key_mutex_blackhole,

storage/example/ha_example.cc

@@ -262,6 +262,7 @@ static int example_init_func(void *p)
   example_hton->table_options= example_table_option_list;
   example_hton->field_options= example_field_option_list;
   example_hton->tablefile_extensions= ha_example_exts;
+  example_hton->drop_table= [](handlerton *, const char*) { return 0; };
 
   DBUG_RETURN(0);
 }

storage/federated/ha_federated.cc

@@ -484,6 +484,7 @@ int federated_db_init(void *p)
   federated_hton->commit= federated_commit;
   federated_hton->rollback= federated_rollback;
   federated_hton->create= federated_create_handler;
+  federated_hton->drop_table= [](handlerton *, const char*) { return 0; };
   federated_hton->flags= (HTON_ALTER_NOT_SUPPORTED | HTON_NO_PARTITION |
                           HTON_AUTOMATIC_DELETE_TABLE);
 

storage/federatedx/ha_federatedx.cc

@@ -438,6 +438,7 @@ int federatedx_db_init(void *p)
   federatedx_hton->rollback= ha_federatedx::rollback;
   federatedx_hton->discover_table_structure= ha_federatedx::discover_assisted;
   federatedx_hton->create= federatedx_create_handler;
+  federatedx_hton->drop_table= [](handlerton *, const char*) { return 0; };
   federatedx_hton->flags= (HTON_ALTER_NOT_SUPPORTED |
                            HTON_AUTOMATIC_DELETE_TABLE);
   federatedx_hton->create_derived= create_federatedx_derived_handler;

storage/heap/ha_heap.cc

@@ -34,12 +34,18 @@ heap_prepare_hp_create_info(TABLE *table_arg, bool internal_table,
                             HP_CREATE_INFO *hp_create_info);
 
 
-int heap_panic(handlerton *hton, ha_panic_function flag)
+static int heap_panic(handlerton *hton, ha_panic_function flag)
 {
   return hp_panic(flag);
 }
 
 
+static int heap_drop_table(handlerton *hton, const char *path)
+{
+  int error= heap_delete_table(path);
+  return error == ENOENT ? 0 : error;
+}
+
 int heap_init(void *p)
 {
   handlerton *heap_hton;
@@ -50,6 +56,7 @@ int heap_init(void *p)
   heap_hton->db_type=    DB_TYPE_HEAP;
   heap_hton->create=     heap_create_handler;
   heap_hton->panic=      heap_panic;
+  heap_hton->drop_table= heap_drop_table;
   heap_hton->flags=      HTON_CAN_RECREATE;
 
   return 0;
@@ -559,8 +566,7 @@ THR_LOCK_DATA **ha_heap::store_lock(THD *thd,
 
 int ha_heap::delete_table(const char *name)
 {
-  int error= heap_delete_table(name);
-  return error == ENOENT ? 0 : error;
+  return heap_drop_table(0, name);
 }
 
 

storage/myisam/ha_myisam.cc

@@ -2512,6 +2512,11 @@ int myisam_panic(handlerton *hton, ha_panic_function flag)
   return mi_panic(flag);
 }
 
+static int myisam_drop_table(handlerton *hton, const char *path)
+{
+  return mi_delete_table(path);
+}
+
 static int myisam_init(void *p)
 {
   handlerton *hton;
@@ -2529,6 +2534,7 @@ static int myisam_init(void *p)
   hton= (handlerton *)p;
   hton->db_type= DB_TYPE_MYISAM;
   hton->create= myisam_create_handler;
+  hton->drop_table= myisam_drop_table;
   hton->panic= myisam_panic;
   hton->flags= HTON_CAN_RECREATE | HTON_SUPPORT_LOG_TABLES;
   hton->tablefile_extensions= ha_myisam_exts;

storage/oqgraph/ha_oqgraph.cc

@@ -192,6 +192,7 @@ static int oqgraph_init(void *p)
   hton->discover_table_structure= oqgraph_discover_table_structure;
 
   hton->close_connection = oqgraph_close_connection;
+  hton->drop_table= [](handlerton *, const char*) { return 0; };
 
   oqgraph_init_done= TRUE;
   return 0;

storage/perfschema/ha_perfschema.cc

@@ -94,6 +94,7 @@ static int pfs_init_func(void *p)
   pfs_hton= reinterpret_cast<handlerton *> (p);
 
   pfs_hton->create= pfs_create_handler;
+  pfs_hton->drop_table= [](handlerton *, const char*) { return 0; };
   pfs_hton->show_status= pfs_show_status;
   pfs_hton->flags= (HTON_ALTER_NOT_SUPPORTED |
                     HTON_TEMPORARY_NOT_SUPPORTED |

storage/sequence/sequence.cc

@@ -502,6 +502,7 @@ static int init(void *p)
   handlerton *hton= (handlerton *)p;
   sequence_hton= hton;
   hton->create= create_handler;
+  hton->drop_table= [](handlerton *, const char*) { return 0; };
   hton->discover_table= discover_table;
   hton->discover_table_existence= discover_table_existence;
   hton->commit= hton->rollback= dummy_commit_rollback;

storage/sphinx/ha_sphinx.cc

@@ -749,6 +749,7 @@ static int sphinx_init_func ( void * p )
 		hton->close_connection = sphinx_close_connection;
 		hton->show_status = sphinx_show_status;
 		hton->panic = sphinx_panic;
+		hton->drop_table= [](handlerton *, const char*) { return 0; };
 		hton->flags = HTON_CAN_RECREATE | HTON_AUTOMATIC_DELETE_TABLE;
 		#endif
 	}