title: Frame Animation failing with Resources$NotFoundException
body: <p>I am just trying to insert a frame by frame animation created using images now in webp format which runs fine with the below given piece of code on Android 7.1 Oneplus3 but fails on Android 4.1.1 (Emulator) with the ResourcesNotFoundException saying that it cannot find the xml file with the name animation.xml in drawable folder. I just have one drawable folder in my project I also added <code>vectorDrawables.useSupportLibrary = true</code> as one of stackoverflow threads suggested, I cleaned project and also tried android:largeHeap="true" even though the image sizes are too small but the error persists on 4.1.1 android api.</p>
  
  <pre><code>imageView = (ImageView) findViewById(R.id.animx);
  
  imageView.setBackgroundResource(R.drawable.animation); // error happening here
  AnimationDrawable anim = (AnimationDrawable) imageView.getBackground(); 
  anim.start();
  </code></pre>
  
  <p>The drawable/animation.xml file looks like this :</p>
  
  <pre><code>    &lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;animation-list xmlns:android="http://schemas.android.com/apk/res/android"
      android:oneshot="false"&gt;
      &lt;item android:drawable="@drawable/spinners1" android:duration="70" /&gt;
      &lt;item android:drawable="@drawable/spinners2" android:duration="70" /&gt;
      &lt;item android:drawable="@drawable/spinners3" android:duration="70" /&gt;
      &lt;item android:drawable="@drawable/spinners4" android:duration="70" /&gt;
  &lt;/animation-list&gt;
  </code></pre>
  
  <p>What is the reason for the crash? Why is it only happening in Android 4.1.1? Also will there be any compatibility issue for lower android versions if I use <code>vectorDrawables.useSupportLibrary = true</code> as I am supporting devices since Gingerbread?
  It would be obvious to add but the files including images and xml are present in the project files. </p>