title: Attempt to invoke interface method 'void android.view.inputmethod.InputConnection.closeConnection()' on a null object reference
body: <p>environment:Android Studio 3.1.1
  code:</p>
  
  <pre><code>import com.firebase.ui.auth.AuthUI;
  ...
      private void startSignIn()
      {
          // Sign in with FirebaseUI
          Intent intent = AuthUI.getInstance()
                  .createSignInIntentBuilder()
                  .setIsSmartLockEnabled(false)
                  .setAvailableProviders(Arrays.asList(
                          new AuthUI.IdpConfig.EmailBuilder().build(),
                          new AuthUI.IdpConfig.GoogleBuilder().build()
                  ))
                  .build();
  
          startActivityForResult(intent, RC_SIGN_IN);
          mViewModel.setIsSigningIn(true);
  
      }
  </code></pre>
  
  <p>The bug appeared when I deleted my account in firebase>Authentication>USERS and tried to sign up with the same email again.</p>
  
  <p>When I choose sign in with email and input an email and push "Next"
  the app has stopped...</p>
  
  <p>it should be creat an new account</p>
  
  <p>errorcode：</p>
  
  <pre><code>java.lang.NullPointerException: Attempt to invoke interface method 'void android.view.inputmethod.InputConnection.closeConnection()' on a null object reference
          at android.view.inputmethod.InputConnectionWrapper.closeConnection(InputConnectionWrapper.java:270)
          at com.android.internal.view.IInputConnectionWrapper.executeMessage(IInputConnectionWrapper.java:541)
          at com.android.internal.view.IInputConnectionWrapper$MyHandler.handleMessage(IInputConnectionWrapper.java:85)
          at android.os.Handler.dispatchMessage(Handler.java:106)
          at android.os.Looper.loop(Looper.java:164)
          at android.app.ActivityThread.main(ActivityThread.java:6494)
          at java.lang.reflect.Method.invoke(Native Method)
          at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:438)
          at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:807)
  </code></pre>
  
  <p>any idea what's goes wrong?</p>