Fixed some broken tests in HHVM for different behavior in SplFixedArray

src/ORM/ResultSet.php

@@ -217,7 +217,7 @@ class ResultSet implements ResultSetInterface
      */
     public function valid()
     {
-        if (isset($this->_results[$this->_index])) {
+        if ($this->_results[$this->_index] !== null) {
             $this->_current = $this->_results[$this->_index];
             return true;
         }

tests/TestCase/ORM/Behavior/CounterCacheBehaviorTest.php

@@ -385,7 +385,7 @@ class CounterCacheBehaviorTest extends TestCase
      */
     protected function _getUser($id = 1)
     {
-        return $this->user->find('all')->where(['id' => $id])->first();
+        return $this->user->get($id);
     }
 
     /**