Minor language-specific case tweaks (#2396)

lib/custom_errors.dart

@@ -5,6 +5,7 @@ import 'package:easy_localization/easy_localization.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
 import 'package:obtainium/providers/logs_provider.dart';
+import 'package:obtainium/providers/source_provider.dart';
 import 'package:provider/provider.dart';
 
 class ObtainiumError {
@@ -158,7 +159,7 @@ void showError(dynamic e, BuildContext context) {
 }
 
 String list2FriendlyString(List<String> list) {
-  var isEnglish = tr('and') == 'and'; // Quick hack, find better way;
+  var isUsingEnglish = isEnglish();
   return list.length == 2
       ? '${list[0]} ${tr('and')} ${list[1]}'
       : list
@@ -170,7 +171,7 @@ String list2FriendlyString(List<String> list) {
                   (e.key == list.length - 1
                       ? ''
                       : e.key == list.length - 2
-                      ? '${isEnglish ? ',' : ''} and '
+                      ? '${isUsingEnglish ? ',' : ''} and '
                       : ', '),
             )
             .join('');

lib/pages/app.dart

@@ -232,7 +232,10 @@ class _AppPageState extends State<AppPage> {
                         : const EdgeInsetsDirectional.fromSTEB(0, 6, 0, 6),
                     margin: const EdgeInsetsDirectional.fromSTEB(0, 6, 0, 0),
                     child: Text(
-                      tr('downloadX', args: [tr('releaseAsset').toLowerCase()]),
+                      tr(
+                        'downloadX',
+                        args: [lowerCaseIfEnglish(tr('releaseAsset'))],
+                      ),
                       textAlign: TextAlign.center,
                       style: Theme.of(context).textTheme.labelSmall!.copyWith(
                         decoration: TextDecoration.underline,

lib/pages/apps.dart

@@ -1072,7 +1072,10 @@ class AppsPageState extends State<AppsPage> {
                       Navigator.of(context).pop();
                     },
                     child: Text(
-                      tr('downloadX', args: [tr('releaseAsset').toLowerCase()]),
+                      tr(
+                        'downloadX',
+                        args: [lowerCaseIfEnglish(tr('releaseAsset'))],
+                      ),
                     ),
                   ),
                   const Divider(),

lib/pages/import_export.dart

@@ -545,7 +545,7 @@ class _ImportExportPageState extends State<ImportExportPage> {
                                 child: Text(
                                   tr(
                                     'searchX',
-                                    args: [tr('source').toLowerCase()],
+                                    args: [lowerCaseIfEnglish(tr('source'))],
                                   ),
                                 ),
                               ),

lib/providers/apps_provider.dart

@@ -2164,7 +2164,7 @@ class _AppFilePickerState extends State<AppFilePicker> {
       scrollable: true,
       title: Text(
         widget.pickAnyAsset
-            ? tr('selectX', args: [tr('releaseAsset').toLowerCase()])
+            ? tr('selectX', args: [lowerCaseIfEnglish(tr('releaseAsset'))])
             : tr('pickAnAPK'),
       ),
       content: Column(

lib/providers/source_provider.dart

@@ -1052,6 +1052,9 @@ List<MapEntry<String, String>> filterApks(
   return apkUrls;
 }
 
+bool isEnglish() => tr('and') == 'and'; // Quick hack, find a better way
+String lowerCaseIfEnglish(String str) => isEnglish() ? str.toLowerCase() : str;
+
 bool isVersionPseudo(App app) =>
     app.additionalSettings['trackOnly'] == true ||
     (app.installedVersion != null &&