MDEV-29277 On error, fts_sync_table() fails to release a table handle

 fts_sync_commit() fails to release the auxiliary table handle
when it encounters error. This issue is caused by
commit 1fd7d3a9(MDEV-25581).
fts_cache_clear() releases the auxiliary table handles.
MDEV-25581's patch clear the cache only if fts_sync_commit was
successful.

storage/innobase/fts/fts0fts.cc

@@ -3960,6 +3960,43 @@ fts_sync_index(
 	return(fts_sync_write_words(trx, index_cache));
 }
 
+/** Rollback a sync operation
+@param[in,out]	sync	sync state */
+static
+void
+fts_sync_rollback(
+	fts_sync_t*	sync)
+{
+	trx_t*		trx = sync->trx;
+	fts_cache_t*	cache = sync->table->fts->cache;
+
+	for (ulint i = 0; i < ib_vector_size(cache->indexes); ++i) {
+		ulint			j;
+		fts_index_cache_t*	index_cache;
+
+		index_cache = static_cast<fts_index_cache_t*>(
+			ib_vector_get(cache->indexes, i));
+
+		for (j = 0; fts_index_selector[j].value; ++j) {
+
+			if (index_cache->ins_graph[j] != NULL) {
+
+				que_graph_free(index_cache->ins_graph[j]);
+
+				index_cache->ins_graph[j] = NULL;
+			}
+		}
+	}
+
+	mysql_mutex_unlock(&cache->lock);
+
+	fts_sql_rollback(trx);
+
+	/* Avoid assertion in trx_t::free(). */
+	trx->dict_operation_lock_mode = false;
+	trx->free();
+}
+
 /** Commit the SYNC, change state of processed doc ids etc.
 @param[in,out]	sync	sync state
 @return DB_SUCCESS if all OK */
@@ -4000,10 +4037,10 @@ fts_sync_commit(
 		mysql_mutex_unlock(&cache->lock);
 		fts_sql_commit(trx);
 	} else {
-		mysql_mutex_unlock(&cache->lock);
-		fts_sql_rollback(trx);
 		ib::error() << "(" << error << ") during SYNC of "
 			"table " << sync->table->name;
+		fts_sync_rollback(sync);
+		return error;
 	}
 
 	if (UNIV_UNLIKELY(fts_enable_diag_print) && elapsed_time) {
@@ -4023,43 +4060,6 @@ fts_sync_commit(
 	return(error);
 }
 
-/** Rollback a sync operation
-@param[in,out]	sync	sync state */
-static
-void
-fts_sync_rollback(
-	fts_sync_t*	sync)
-{
-	trx_t*		trx = sync->trx;
-	fts_cache_t*	cache = sync->table->fts->cache;
-
-	for (ulint i = 0; i < ib_vector_size(cache->indexes); ++i) {
-		ulint			j;
-		fts_index_cache_t*	index_cache;
-
-		index_cache = static_cast<fts_index_cache_t*>(
-			ib_vector_get(cache->indexes, i));
-
-		for (j = 0; fts_index_selector[j].value; ++j) {
-
-			if (index_cache->ins_graph[j] != NULL) {
-
-				que_graph_free(index_cache->ins_graph[j]);
-
-				index_cache->ins_graph[j] = NULL;
-			}
-		}
-	}
-
-	mysql_mutex_unlock(&cache->lock);
-
-	fts_sql_rollback(trx);
-
-	/* Avoid assertion in trx_t::free(). */
-	trx->dict_operation_lock_mode = false;
-	trx->free();
-}
-
 /** Run SYNC on the table, i.e., write out data from the cache to the
 FTS auxiliary INDEX table and clear the cache at the end.
 @param[in,out]	sync		sync state