GoBackend: integrate into app

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

app/src/main/java/com/wireguard/android/activity/SettingsActivity.java

@@ -2,9 +2,12 @@ package com.wireguard.android.activity;
 
 import android.app.Activity;
 import android.os.Bundle;
+import android.preference.Preference;
 import android.preference.PreferenceFragment;
 
+import com.wireguard.android.Application;
 import com.wireguard.android.R;
+import com.wireguard.android.backend.WgQuickBackend;
 
 /**
  * Interface for changing application-global persistent settings.
@@ -26,6 +29,11 @@ public class SettingsActivity extends Activity {
         public void onCreate(final Bundle savedInstanceState) {
             super.onCreate(savedInstanceState);
             addPreferencesFromResource(R.xml.preferences);
+            if (Application.getComponent().getBackendType() != WgQuickBackend.class) {
+                final Preference toolsInstaller =
+                        getPreferenceManager().findPreference("tools_installer");
+                getPreferenceScreen().removePreference(toolsInstaller);
+            }
         }
     }
 }