title: Android error during build - "default public constructor with no argument must be declared". What's the cause?
body: <p>Android studio returned an error during build, even after running Clean, and rebuilding:</p>
  
  <blockquote>
    <p>A default public constructor with no argument must be declared if a
    custom constructor is declared.</p>
  </blockquote>
  
  <p>I could not find a line number, nor a file referenced. I have no idea what causes this, as there's no indication from the build where or what the cause of this is.</p>