CW-351-Add-option-in-Privacy-settings-to-enable-disable-screenshots (#885)

* add prevent screenshots option

* fix prevent screen recording

* update localization

* Update strings_ja.arb

lib/src/screens/settings/privacy_page.dart

@@ -8,6 +8,7 @@ import 'package:cake_wallet/view_model/settings/choices_list_item.dart';
 import 'package:cake_wallet/view_model/settings/privacy_settings_view_model.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_mobx/flutter_mobx.dart';
+import 'dart:io' show Platform;
 
 class PrivacyPage extends BasePage {
   PrivacyPage(this._privacySettingsViewModel);
@@ -48,6 +49,13 @@ class PrivacyPage extends BasePage {
                 onValueChange: (BuildContext _, bool value) {
                   _privacySettingsViewModel.setShouldSaveRecipientAddress(value);
                 }),
+            if (Platform.isAndroid)
+            SettingsSwitcherCell(
+                title: S.current.prevent_screenshots,
+                value: _privacySettingsViewModel.isAppSecure,
+                onValueChange: (BuildContext _, bool value) {
+                  _privacySettingsViewModel.setIsAppSecure(value);
+                }),
           ],
         );
       }),