title: What is com.android.vending.BILLING, how to use it?
body: <p>I found some application use permission com.android.vending.BILLING,</p>
  
  <pre><code>uses-permission:'com.android.vending.BILLING'
  </code></pre>
  
  <p>I cannot find any infomation in source code and Google.</p>
  
  <p>What is it? How to use it?</p>