makes suggested changes

app/src/main/java/chat/rocket/android/activity/LoginActivity.java

 package chat.rocket.android.activity;
 
-import android.content.Context;
 import android.content.Intent;
 import android.os.Bundle;
 import android.support.annotation.Nullable;
@@ -100,8 +99,7 @@ public class LoginActivity extends AbstractFragmentActivity implements LoginCont
         } else if (BackStackHelper.FRAGMENT_TAG.equals("login")) {
             LoginFragment loginFragment = (LoginFragment) getSupportFragmentManager()
                     .findFragmentById(getLayoutContainerForFragment());
-            Context loginActivityContext = this;
-            loginFragment.goBack(loginActivityContext);
+            loginFragment.goBack();
         }
         return true;
     }

app/src/main/java/chat/rocket/android/fragment/server_config/LoginContract.java

@@ -26,7 +26,7 @@ public interface LoginContract {
 
         void showTwoStepAuth();
 
-        void goBack(Context ctx);
+        void goBack();
     }
 
     interface Presenter extends BaseContract.Presenter<View> {

app/src/main/java/chat/rocket/android/fragment/server_config/LoginFragment.kt

 package chat.rocket.android.fragment.server_config
 
-import android.content.Context
 import android.os.Bundle
 import android.support.constraint.ConstraintLayout
 import android.support.design.widget.Snackbar
@@ -161,8 +160,9 @@ class LoginFragment : AbstractServerConfigFragment(), LoginContract.View {
         presenter.release()
         super.onPause()
     }
-    override fun goBack(ctx: Context?) {
-        presenter.goBack(ctx)
+    
+    override fun goBack() {
+        presenter.goBack(context)
     }
 
 }

app/src/main/java/chat/rocket/android/fragment/server_config/LoginPresenter.kt

@@ -33,7 +33,7 @@ class LoginPresenter(private val loginServiceConfigurationRepository: LoginServi
     }
 
 
-    override fun goBack(ctx : Context?) {
+    override fun goBack(ctx: Context?) {
         val context = RocketChatApplication.getInstance()
         val hostname = RocketChatCache.getSelectedServerHostname()
         hostname?.let {

app/src/main/java/chat/rocket/android/helper/BackStackHelper.java

 package chat.rocket.android.helper;
 
-/**
- * Created by whocares on 28/12/17.
- */
 
 public class BackStackHelper {
     public static String FRAGMENT_TAG = "login";