title: Cannot resolve symbol nullable
body: <p>Getting cannot resolve symbol nullable error for my program.
  @androidx.annotations.Nullable - nullable has redline under it.</p>
  
  <pre><code>package com.singularity.birdjumper;
  
  import android.app.Activity;
  import android.os.Bundle;
  
  public class GameActivity extends Activity
  {
      @Override
      protected void onCreate(@androidx.annotation.Nullable Bundle savedInstanceState) {
          super.onCreate(savedInstanceState);
      }
  }
  </code></pre>