Reverted changes since it was an error from my end

Author: chaitanya-bhagavan

lib/modules/database.js

@@ -232,7 +232,7 @@ class DatabaseRef extends ReferenceBase {
     const path = this.dbPath();
     return this.db.off(path, evt, origCB)
       .then(({callback, subscriptions}) => {
-        if (subscriptions[path] && subscriptions[path][evt].length > 0) {
+        if (dbSubscriptions[path] && dbSubscriptions[path][evt].length > 0) {
           return subscriptions;
         }