Pass cancellation token to connection opening

Author: alex-kulakov

Orm/Xtensive.Orm/Orm/Providers/StorageDriver.Operations.cs

@@ -124,10 +124,10 @@ public void EnsureConnectionIsOpen(Session session, SqlConnection connection)
       }
     }
 
-    public async Task EnsureConnectionIsOpenAsync(Session session, SqlConnection connection)
+    public async Task EnsureConnectionIsOpenAsync(Session session, SqlConnection connection, CancellationToken token)
     {
       if (connection.State != ConnectionState.Open) {
-        await OpenConnectionAsync(session, connection).ConfigureAwait(false);
+        await OpenConnectionAsync(session, connection, token).ConfigureAwait(false);
       }
     }