[android] StartupActivity: Address first round of review comments

briar-android/src/main/java/org/briarproject/briar/android/BriarApplication.java

 package org.briarproject.briar.android;
 
+import android.app.Activity;
 import android.content.SharedPreferences;
 
+import org.briarproject.briar.android.navdrawer.NavDrawerActivity;
+
 import java.util.Collection;
 import java.util.logging.LogRecord;
 
@@ -11,6 +14,8 @@ import java.util.logging.LogRecord;
  */
 public interface BriarApplication {
 
+	Class<? extends Activity> ENTRY_ACTIVITY = NavDrawerActivity.class;
+
 	Collection<LogRecord> getRecentLogRecords();
 
 	AndroidComponent getApplicationComponent();

briar-android/src/main/java/org/briarproject/briar/android/BriarService.java

@@ -47,7 +47,7 @@ import static java.util.logging.Level.INFO;
 import static java.util.logging.Level.WARNING;
 import static org.briarproject.bramble.api.lifecycle.LifecycleManager.StartResult.ALREADY_RUNNING;
 import static org.briarproject.bramble.api.lifecycle.LifecycleManager.StartResult.SUCCESS;
-import static org.briarproject.briar.android.activity.ActivityComponent.ENTRY_ACTIVITY;
+import static org.briarproject.briar.android.BriarApplication.ENTRY_ACTIVITY;
 import static org.briarproject.briar.api.android.AndroidNotificationManager.FAILURE_CHANNEL_ID;
 import static org.briarproject.briar.api.android.AndroidNotificationManager.FAILURE_NOTIFICATION_ID;
 import static org.briarproject.briar.api.android.AndroidNotificationManager.ONGOING_CHANNEL_ID;

briar-android/src/main/java/org/briarproject/briar/android/StartupFailureActivity.java

@@ -74,7 +74,7 @@ public class StartupFailureActivity extends BaseActivity implements
 
 	@Override
 	public void runOnDbThread(@NonNull Runnable runnable) {
-		throw new AssertionError("Deprecated and should not be used");
+		throw new UnsupportedOperationException();
 	}
 
 }

briar-android/src/main/java/org/briarproject/briar/android/account/SetupActivity.java

@@ -19,7 +19,7 @@ import static android.content.Intent.FLAG_ACTIVITY_CLEAR_TASK;
 import static android.content.Intent.FLAG_ACTIVITY_CLEAR_TOP;
 import static android.content.Intent.FLAG_ACTIVITY_NEW_TASK;
 import static android.content.Intent.FLAG_ACTIVITY_TASK_ON_HOME;
-import static org.briarproject.briar.android.activity.ActivityComponent.ENTRY_ACTIVITY;
+import static org.briarproject.briar.android.BriarApplication.ENTRY_ACTIVITY;
 
 @MethodsNotNullByDefault
 @ParametersNotNullByDefault

briar-android/src/main/java/org/briarproject/briar/android/activity/ActivityComponent.java

@@ -91,8 +91,6 @@ import dagger.Component;
 		dependencies = AndroidComponent.class)
 public interface ActivityComponent {
 
-	Class<? extends Activity> ENTRY_ACTIVITY = NavDrawerActivity.class;
-
 	Activity activity();
 
 	void inject(SplashScreenActivity activity);

briar-android/src/main/java/org/briarproject/briar/android/login/OpenDatabaseFragment.java

@@ -26,7 +26,7 @@ import static org.briarproject.briar.android.login.StartupViewModel.State.MIGRAT
 @ParametersNotNullByDefault
 public class OpenDatabaseFragment extends BaseFragment {
 
-	final static String TAG = PasswordFragment.class.getName();
+	final static String TAG = OpenDatabaseFragment.class.getName();
 
 	@Inject
 	ViewModelProvider.Factory viewModelFactory;

briar-android/src/main/java/org/briarproject/briar/android/login/StartupActivity.java

@@ -23,6 +23,7 @@ import javax.inject.Inject;
 import static android.content.Intent.FLAG_ACTIVITY_CLEAR_TASK;
 import static android.content.Intent.FLAG_ACTIVITY_CLEAR_TOP;
 import static android.content.Intent.FLAG_ACTIVITY_NEW_TASK;
+import static android.content.Intent.FLAG_ACTIVITY_TASK_ON_HOME;
 import static org.briarproject.briar.android.login.StartupViewModel.State.SIGNED_IN;
 import static org.briarproject.briar.android.login.StartupViewModel.State.SIGNED_OUT;
 import static org.briarproject.briar.android.login.StartupViewModel.State.STARTED;
@@ -59,10 +60,12 @@ public class StartupActivity extends BaseActivity implements
 			// because if it exists, we assume the database also exists
 			// and when clearing app data, the folder does not get deleted.
 			viewModel.deleteAccount();
-			onAccountDeleted(true);
+			onAccountDeleted();
 			return;
 		}
-		viewModel.getAccountDeleted().observe(this, this::onAccountDeleted);
+		viewModel.getAccountDeleted().observe(this, deleted -> {
+			if (deleted != null && deleted) onAccountDeleted();
+		});
 		viewModel.getState().observe(this, this::onStateChanged);
 	}
 
@@ -86,7 +89,10 @@ public class StartupActivity extends BaseActivity implements
 		} else if (state == SIGNED_IN) {
 			startService(new Intent(this, BriarService.class));
 		} else if (state == STARTING) {
-			// only show OpenDatabaseFragment if not already visible
+			// Only show OpenDatabaseFragment if not already visible.
+			// This can happen because several LifecycleManager states are
+			// mapped to STARTING, so this can get called several times
+			// as the app's lifecycle advances.
 			FragmentManager fm = getSupportFragmentManager();
 			Fragment f = fm.findFragmentByTag(OpenDatabaseFragment.TAG);
 			if (f == null || !f.isVisible()) {
@@ -100,21 +106,19 @@ public class StartupActivity extends BaseActivity implements
 		}
 	}
 
-	private void onAccountDeleted(boolean accountDeleted) {
-		if (accountDeleted) {
-			setResult(RESULT_CANCELED);
-			finish();
-			Intent i = new Intent(this, SetupActivity.class);
-			i.addFlags(FLAG_ACTIVITY_NEW_TASK | FLAG_ACTIVITY_CLEAR_TOP |
-					FLAG_ACTIVITY_CLEAR_TASK);
-			startActivity(i);
-		}
+	private void onAccountDeleted() {
+		setResult(RESULT_CANCELED);
+		finish();
+		Intent i = new Intent(this, SetupActivity.class);
+		i.addFlags(FLAG_ACTIVITY_NEW_TASK | FLAG_ACTIVITY_CLEAR_TOP |
+				FLAG_ACTIVITY_CLEAR_TASK | FLAG_ACTIVITY_TASK_ON_HOME);
+		startActivity(i);
 	}
 
 	@Override
 	public void runOnDbThread(Runnable runnable) {
 		// we don't need this and shouldn't be forced to implement it
-		throw new AssertionError();
+		throw new UnsupportedOperationException();
 	}
 
 }

briar-android/src/main/java/org/briarproject/briar/android/settings/SettingsFragment.java

@@ -52,6 +52,7 @@ import javax.inject.Inject;
 
 import static android.app.Activity.RESULT_OK;
 import static android.content.Intent.FLAG_ACTIVITY_CLEAR_TASK;
+import static android.content.Intent.FLAG_ACTIVITY_CLEAR_TOP;
 import static android.content.Intent.FLAG_ACTIVITY_NEW_TASK;
 import static android.media.RingtoneManager.ACTION_RINGTONE_PICKER;
 import static android.media.RingtoneManager.EXTRA_RINGTONE_DEFAULT_URI;
@@ -79,7 +80,7 @@ import static org.briarproject.bramble.util.LogUtils.logDuration;
 import static org.briarproject.bramble.util.LogUtils.logException;
 import static org.briarproject.bramble.util.LogUtils.now;
 import static org.briarproject.briar.android.TestingConstants.IS_DEBUG_BUILD;
-import static org.briarproject.briar.android.activity.ActivityComponent.ENTRY_ACTIVITY;
+import static org.briarproject.briar.android.BriarApplication.ENTRY_ACTIVITY;
 import static org.briarproject.briar.android.activity.RequestCodes.REQUEST_RINGTONE;
 import static org.briarproject.briar.android.navdrawer.NavDrawerActivity.INTENT_SIGN_OUT;
 import static org.briarproject.briar.android.util.UiUtils.hasScreenLock;
@@ -576,7 +577,7 @@ public class SettingsFragment extends PreferenceFragmentCompat
 				(dialogInterface, i) -> {
 					language.setValue(newValue);
 					Intent intent = new Intent(getContext(), ENTRY_ACTIVITY);
-					intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
+					intent.setFlags(FLAG_ACTIVITY_CLEAR_TOP);
 					intent.putExtra(INTENT_SIGN_OUT, true);
 					requireActivity().startActivity(intent);
 					requireActivity().finish();

briar-android/src/main/java/org/briarproject/briar/android/splash/SplashScreenActivity.java

@@ -26,7 +26,7 @@ import static android.support.v7.preference.PreferenceManager.setDefaultValues;
 import static java.lang.System.currentTimeMillis;
 import static java.util.logging.Logger.getLogger;
 import static org.briarproject.briar.android.TestingConstants.EXPIRY_DATE;
-import static org.briarproject.briar.android.activity.ActivityComponent.ENTRY_ACTIVITY;
+import static org.briarproject.briar.android.BriarApplication.ENTRY_ACTIVITY;
 
 @MethodsNotNullByDefault
 @ParametersNotNullByDefault

briar-android/src/main/java/org/briarproject/briar/android/test/TestDataActivity.java

@@ -16,7 +16,7 @@ import org.briarproject.briar.api.test.TestDataCreator;
 import javax.inject.Inject;
 
 import static android.content.Intent.FLAG_ACTIVITY_CLEAR_TOP;
-import static org.briarproject.briar.android.activity.ActivityComponent.ENTRY_ACTIVITY;
+import static org.briarproject.briar.android.BriarApplication.ENTRY_ACTIVITY;
 
 public class TestDataActivity extends BriarActivity {