Add e2ee settings

lib/components/dialogs/confirm_dialog.dart

@@ -0,0 +1,36 @@
+import 'package:fluffychat/i18n/i18n.dart';
+import 'package:flutter/material.dart';
+
+class ConfirmDialog extends StatelessWidget {
+  const ConfirmDialog(
+    this.text,
+    this.confirmText,
+    this.onConfirmed,
+  );
+  final String text;
+  final String confirmText;
+  final Function(BuildContext) onConfirmed;
+
+  @override
+  Widget build(BuildContext context) {
+    return AlertDialog(
+      title: Text(text),
+      actions: <Widget>[
+        FlatButton(
+          child: Text(I18n.of(context).close.toUpperCase(),
+              style: TextStyle(color: Colors.blueGrey)),
+          onPressed: () => Navigator.of(context).pop(),
+        ),
+        FlatButton(
+          child: Text(
+            confirmText.toUpperCase(),
+          ),
+          onPressed: () {
+            Navigator.of(context).pop();
+            onConfirmed(context);
+          },
+        ),
+      ],
+    );
+  }
+}