Merge branch 'feature-flags' into 'master'

Add feature flag for dark theme

See merge request briar/briar!843

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

@@ -30,4 +30,9 @@ public interface TestingConstants {
 	long EXPIRY_DATE = IS_DEBUG_BUILD || IS_BETA_BUILD ?
 			BuildConfig.BuildTimestamp + 90 * 24 * 60 * 60 * 1000L :
 			Long.MAX_VALUE;
+
+	/**
+	 * Feature flag for enabling the dark UI theme in release builds.
+	 */
+	boolean FEATURE_FLAG_DARK_THEME = false;
 }

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

@@ -70,6 +70,7 @@ import static org.briarproject.bramble.api.plugin.TorConstants.PREF_TOR_NETWORK_
 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.FEATURE_FLAG_DARK_THEME;
 import static org.briarproject.briar.android.TestingConstants.IS_DEBUG_BUILD;
 import static org.briarproject.briar.android.activity.RequestCodes.REQUEST_RINGTONE;
 import static org.briarproject.briar.android.navdrawer.NavDrawerActivity.INTENT_SIGN_OUT;
@@ -197,8 +198,7 @@ public class SettingsFragment extends PreferenceFragmentCompat
 					}
 			);
 		} else {
-			// TODO remove before releasing theme to public
-			theme.setVisible(false);
+			theme.setVisible(FEATURE_FLAG_DARK_THEME);
 
 			findPreference("pref_key_explode").setVisible(false);
 			findPreference("pref_key_test_data").setVisible(false);