Update Mongodb client to 2.2.4 (parse-community#2329)

* chore(package): update mongodb to version 2.2.4

https://greenkeeper.io/

* fix for mongo 2.2.4

* Delete schema promise on error...

- Just because this way we can let the adapter an opportunity to yield a new error....
OR A SUCCESS

* Fixes test

* Restore fix

package.json

@@ -31,7 +31,7 @@
     "lru-cache": "4.0.1",
     "mailgun-js": "0.7.10",
     "mime": "1.3.4",
-    "mongodb": "2.1.18",
+    "mongodb": "2.2.4",
     "multer": "1.1.0",
     "parse": "1.9.0",
     "parse-server-fs-adapter": "1.0.0",

spec/index.spec.js

@@ -65,7 +65,7 @@ describe('server', () => {
         expect(response.statusCode).toEqual(500);
         expect(body.code).toEqual(1);
         expect(body.message).toEqual('Internal server error.');
-        done();
+        reconfigureServer().then(done, done);
       });
     });
   });

src/Controllers/DatabaseController.js

@@ -110,7 +110,8 @@ DatabaseController.prototype.validateClassName = function(className) {
 DatabaseController.prototype.loadSchema = function() {
   if (!this.schemaPromise) {
     this.schemaPromise = SchemaController.load(this.adapter);
-    this.schemaPromise.then(() => delete this.schemaPromise);
+    this.schemaPromise.then(() => delete this.schemaPromise,
+                             () => delete this.schemaPromise);
   }
   return this.schemaPromise;
 };