Simplified quick_rm_table() and mysql_rename_table()

Replaced obscure FRM_ONLY, NO_FRM_RENAME, NO_HA_TABLE, NO_PAR_TABLE with
straightforward explicit flags:

QRMT_FRM - [re]moves .frm
QRMT_PAR - [re]moves .par
QRMT_HANDLER - calls ha_delete_table()/ha_rename_table() and [re]moves
               high-level indexes
QRMT_DEFAULT - same as QRMT_FRM | QRMT_HANDLER, which is regular table
               drop/rename.

sql/ddl_log.cc

@@ -1985,7 +1985,7 @@ static int ddl_log_execute_action(THD *thd, MEM_ROOT *mem_root,
         the original name failed. Now we have to delete the temporary table
         and restore the backup.
       */
-      quick_rm_table(thd, hton, &db, &table, FN_IS_TMP);
+      quick_rm_table(thd, hton, &db, &table, QRMT_DEFAULT | FN_IS_TMP);
       if (!is_renamed)
       {
         execute_rename_table(ddl_log_entry, file,

sql/sql_base.cc

@@ -1461,7 +1461,7 @@ void drop_open_table(THD *thd, TABLE *table, const LEX_CSTRING *db_name,
     table->s->tdc->flush(thd, true);
     close_thread_table(thd, &thd->open_tables);
     /* Remove the table from the storage engine and rm the .frm. */
-    quick_rm_table(thd, table_type, db_name, table_name, 0);
+    quick_rm_table(thd, table_type, db_name, table_name, QRMT_DEFAULT);
  }
   DBUG_VOID_RETURN;
 }

sql/sql_insert.cc

@@ -4769,7 +4769,7 @@ TABLE *select_create::create_table_from_items(THD *thd, List<Item> *items,
       {
         quick_rm_table(thd, create_info->db_type, &table_list->db,
                        table_case_name(create_info, &table_list->table_name),
-                       0);
+                       QRMT_DEFAULT);
       }
       /* Restore */
       table_list->open_strategy= save_open_strategy;

sql/sql_rename.cc

@@ -299,7 +299,7 @@ check_rename(THD *thd, rename_param *param,
       Discovery will find the old table when it's accessed
      */
     tdc_remove_table(thd, ren_table->db.str, ren_table->table_name.str);
-    quick_rm_table(thd, 0, &ren_table->db, &param->old_alias, FRM_ONLY, 0);
+    quick_rm_table(thd, 0, &ren_table->db, &param->old_alias, QRMT_FRM);
     DBUG_RETURN(-1);
   }
 
@@ -380,7 +380,8 @@ do_rename(THD *thd, const rename_param *param, DDL_LOG_STATE *ddl_log_state,
 
     debug_crash_here("ddl_log_rename_before_rename_table");
     if (!(rc= mysql_rename_table(hton, &ren_table->db, old_alias,
-                                 new_db, new_alias, &param->old_version, 0)))
+                                 new_db, new_alias, &param->old_version,
+                                 QRMT_DEFAULT)))
     {
       /* Table rename succeded.
          It's safe to start recovery at rename trigger phase
@@ -415,7 +416,7 @@ do_rename(THD *thd, const rename_param *param, DDL_LOG_STATE *ddl_log_state,
         debug_crash_here("ddl_log_rename_after_failed_rename_trigger");
         (void) mysql_rename_table(hton, new_db, new_alias,
                                   &ren_table->db, old_alias, &param->old_version,
-                                  NO_FK_CHECKS);
+                                  QRMT_DEFAULT | NO_FK_CHECKS);
         debug_crash_here("ddl_log_rename_after_revert_rename_table");
         ddl_log_disable_entry(ddl_log_state);
         debug_crash_here("ddl_log_rename_after_disable_entry");

sql/sql_table.h

@@ -66,16 +66,18 @@ enum enum_explain_filename_mode
 static const uint FN_FROM_IS_TMP=  1 << 0;
 static const uint FN_TO_IS_TMP=    1 << 1;
 static const uint FN_IS_TMP=       FN_FROM_IS_TMP | FN_TO_IS_TMP;
-static const uint NO_FRM_RENAME=   1 << 2;
-static const uint FRM_ONLY=        1 << 3;
-/** Don't remove table in engine. Remove only .FRM and maybe .PAR files. */
-static const uint NO_HA_TABLE=     1 << 4;
+/* Remove .frm table metadata. */
+static constexpr uint QRMT_FRM=       1 << 2;
+/* Remove .par partitioning metadata. */
+static constexpr uint QRMT_PAR=       1 << 3;
+/* Remove handler files and high-level indexes. */
+static constexpr uint QRMT_HANDLER=   1 << 4;
+/* Default behaviour is to drop .FRM and handler, but not .par. */
+static constexpr uint QRMT_DEFAULT=   QRMT_FRM | QRMT_HANDLER;
 /** Don't resolve MySQL's fake "foo.sym" symbolic directory names. */
 static const uint SKIP_SYMDIR_ACCESS= 1 << 5;
 /** Don't check foreign key constraints while renaming table */
 static const uint NO_FK_CHECKS=    1 << 6;
-/* Don't delete .par table in quick_rm_table() */
-static const uint NO_PAR_TABLE=   1 << 7;
 
 uint filename_to_tablename(const char *from, char *to, size_t to_length,
                            bool stay_quiet = false);