title: Issue with scope while upgrade in rails4.2.6 from 4.1.9
body: <p>Issue in rail 4.2.6 during upgrade from <code>rails4.1.9</code> to <code>4.2.6</code>=></p>
  
  <p>I am trying to find those record from a table in which id is same as <code>parent_id</code>.
  So I have written a scope </p>
  
  <pre><code>scope :parent_record, -&gt;{ where(parent_id: self[:id]) } 
  </code></pre>
  
  <p>When I am using this scope and calculating</p>
  
  <pre><code>  self.all.parent_record
  </code></pre>
  
  <p>it returns  <code>"# ActiveRecord::Relation []&gt;"</code></p>
  
  <p>While in rails 4.1.9 it returns - </p>
  
  <pre><code>#ActiveRecord::Relation [#Category id: 6, name: "Business Disruption", description: "", parent_id: 6, status: "a", target_risk: nil, lock_target_risk: false].
  </code></pre>
  
  <p>Ruby version - ruby-2.0.0-p598</p>
  
  <p>Where am I wrong ?</p>