code: public static TypefaceCollection createSystemDefault() {
  		return new Builder()
  				.set(Typeface.NORMAL, Typeface.DEFAULT)
  				.set(Typeface.BOLD, Typeface.DEFAULT_BOLD)
  				.set(Typeface.ITALIC, Typeface.DEFAULT)
  				.set(Typeface.BOLD_ITALIC, Typeface.DEFAULT_BOLD)
  				.create();
  	}
docs: Creates default typeface collection, containing system fonts:
  <ul>
  <li>{@link android.graphics.Typeface#DEFAULT}</li>
  <li>{@link android.graphics.Typeface#DEFAULT_BOLD}</li>
  </ul>
  @return typeface collection