title: What's the purpose of Drawable setHotspot on Android 5.0 (API 21)?
body: <p>Looking at the <a href="https://developer.android.com/reference/android/graphics/drawable/Drawable.html" rel="noreferrer">Drawable</a> docs, we have a new method <code>setHotspot (float x, float y)</code> with the description of:</p>
  
  <blockquote>
    <p>Specifies the hotspot's location within the drawable.</p>
  </blockquote>
  
  <p>With no other explanations on that page, I wonder what the purpose is.</p>