title: Firebase Authentication causing Android fatal exception
body: <p>I just finished integrating Firebase real time data base and Authentication into my Android Studio application. It ran successfully two or three times on my Google Nexus 7 genymotion emulator that has google play services on it. Then I tried launching it again and I started getting the below error: </p>
  
  <pre><code>06-25 16:50:46.994 7699-7699/
  com.careersvirtualsolutions.uprate E/AndroidRuntime: 
  FATAL EXCEPTION: main
  java.lang.NullPointerException
  at com.google.firebase.auth.FirebaseAuth$1.run(Unknown Source)
  at android.os.Handler.handleCallback(Handler.java:730)
  at android.os.Handler.dispatchMessage(Handler.java:92)
  at android.os.Looper.loop(Looper.java:137)
  at android.app.ActivityThread.main(ActivityThread.java:5103)
  at java.lang.reflect.Method.invokeNative(Native Method)
  at java.lang.reflect.Method.invoke(Method.java:525)
  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
  at dalvik.system.NativeStart.main(Native Method)
  </code></pre>
  
  <p>I think this has something to do with the Firebase Authentication SDK but I am not sure.
  Do you know what this is caused by? How can I solve it?</p>