title: How to set background of button back to default_holo_dark
body: <p>I need help for setting a buttons background during runtime to default holo dark.
  When writing the layout, the background can easily be set using <code>@android:drawable/btn_default_holo_dark</code>, but I can't find the corresponding drawable id for btn_default_holo_dark. <code>android.R.drawable.btn_default_holo_dark</code> doesn't exists, and <code>android.R.drawable.btn_default</code> doesn't fits to the holo dark theme.</p>
  
  <p>For solving this problem, I hope you could either tell me the correct id for the button default holo dark style, or another easy way to reset the button to its default theme style (which is holo dark in my case).</p>