Bug #56947 InnoDB leaks memory when failing to create a table

row_create_table_for_mysql(): When the table creation fails,
free the dict_table_t object.

mysql-test/suite/innodb/r/innodb_bug56947.result

+SET @old_innodb_file_per_table=@@innodb_file_per_table;
+SET GLOBAL innodb_file_per_table=0;
+create table bug56947(a int not null) engine = innodb;
+CREATE TABLE `bug56947#1`(a int) ENGINE=InnoDB;
+alter table bug56947 add unique index (a);
+ERROR HY000: Table 'test.bug56947#1' already exists
+drop table `bug56947#1`;
+drop table bug56947;

mysql-test/suite/innodb/t/innodb_bug56947.test

+#
+# Bug #56947 valgrind reports a memory leak in innodb-plugin.innodb-index
+#
+-- source include/have_innodb.inc
+
+SET @old_innodb_file_per_table=@@innodb_file_per_table;
+# avoid a message about filed *.ibd file creation in the error log
+SET GLOBAL innodb_file_per_table=0;
+create table bug56947(a int not null) engine = innodb;
+CREATE TABLE `bug56947#1`(a int) ENGINE=InnoDB;
+--error 156
+alter table bug56947 add unique index (a);
+drop table `bug56947#1`;
+drop table bug56947;
+--disable_query_log
+SET GLOBAL innodb_file_per_table=@old_innodb_file_per_table;

storage/innobase/row/row0mysql.c

@@ -1938,15 +1938,13 @@ err_exit:
 
 	err = trx->error_state;
 
-	if (UNIV_UNLIKELY(err != DB_SUCCESS)) {
+	switch (err) {
+	case DB_SUCCESS:
+		break;
+	case DB_OUT_OF_FILE_SPACE:
 		trx->error_state = DB_SUCCESS;
 		trx_general_rollback_for_mysql(trx, NULL);
-		/* TO DO: free table?  The code below will dereference
-		table->name, though. */
-	}
 
-	switch (err) {
-	case DB_OUT_OF_FILE_SPACE:
 		ut_print_timestamp(stderr);
 		fputs("  InnoDB: Warning: cannot create table ",
 		      stderr);
@@ -1961,9 +1959,13 @@ err_exit:
 		break;
 
 	case DB_DUPLICATE_KEY:
+	default:
 		/* We may also get err == DB_ERROR if the .ibd file for the
 		table already exists */
 
+		trx->error_state = DB_SUCCESS;
+		trx_general_rollback_for_mysql(trx, NULL);
+		dict_mem_table_free(table);
 		break;
 	}