Fix crash on AuthenticationActivity

app/src/main/java/chat/rocket/android/authentication/ui/AuthenticationActivity.kt

@@ -32,17 +32,25 @@ class AuthenticationActivity : AppCompatActivity(), HasSupportFragmentInjector {
         setContentView(R.layout.activity_authentication)
         setTheme(R.style.AuthenticationTheme)
         super.onCreate(savedInstanceState)
+    }
 
+    override fun onStart() {
+        super.onStart()
         val deepLinkInfo = intent.getLoginDeepLinkInfo()
         launch(UI + job) {
             val newServer = intent.getBooleanExtra(INTENT_ADD_NEW_SERVER, false)
             // if we got authenticateWithDeepLink information, pass true to newServer also
             presenter.loadCredentials(newServer || deepLinkInfo != null) { authenticated ->
                 if (!authenticated) {
-                    showServerInput(savedInstanceState, deepLinkInfo)
+                    showServerInput(deepLinkInfo)
+                }
             }
         }
     }
+
+    override fun onStop() {
+        job.cancel()
+        super.onStop()
     }
 
     override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
@@ -53,17 +61,12 @@ class AuthenticationActivity : AppCompatActivity(), HasSupportFragmentInjector {
         }
     }
 
-    override fun onDestroy() {
-        job.cancel()
-        super.onDestroy()
-    }
-
     override fun supportFragmentInjector(): AndroidInjector<Fragment> {
         return fragmentDispatchingAndroidInjector
     }
 
-    fun showServerInput(savedInstanceState: Bundle?, deepLinkInfo: LoginDeepLinkInfo?) {
-        addFragment("ServerFragment", R.id.fragment_container) {
+    fun showServerInput(deepLinkInfo: LoginDeepLinkInfo?) {
+        addFragment("ServerFragment", R.id.fragment_container, allowStateLoss = true) {
             ServerFragment.newInstance(deepLinkInfo)
         }
     }

app/src/main/java/chat/rocket/android/util/extensions/Ui.kt

@@ -31,11 +31,16 @@ fun View.isVisible(): Boolean {
 fun ViewGroup.inflate(@LayoutRes resource: Int, attachToRoot: Boolean = false): View =
     LayoutInflater.from(context).inflate(resource, this, attachToRoot)
 
-fun AppCompatActivity.addFragment(tag: String, layoutId: Int, newInstance: () -> Fragment) {
+fun AppCompatActivity.addFragment(tag: String, layoutId: Int, allowStateLoss: Boolean = false,
+                                  newInstance: () -> Fragment) {
     val fragment = supportFragmentManager.findFragmentByTag(tag) ?: newInstance()
-    supportFragmentManager.beginTransaction()
+    val transaction = supportFragmentManager.beginTransaction()
             .replace(layoutId, fragment, tag)
-        .commit()
+    if (allowStateLoss) {
+        transaction.commitAllowingStateLoss()
+    } else {
+        transaction.commit()
+    }
 }
 
 fun AppCompatActivity.addFragmentBackStack(