refactor: widgets dir

lib/components/connection_status_header.dart

@@ -1,44 +0,0 @@
-import 'dart:async';
-import 'package:flutter/material.dart';
-
-import 'matrix.dart';
-
-class ConnectionStatusHeader extends StatefulWidget {
-  @override
-  _ConnectionStatusHeaderState createState() => _ConnectionStatusHeaderState();
-}
-
-class _ConnectionStatusHeaderState extends State<ConnectionStatusHeader> {
-  StreamSubscription _onSyncSub;
-  StreamSubscription _onSyncErrorSub;
-  static bool _connected = true;
-
-  set connected(bool connected) {
-    if (mounted) {
-      setState(() => _connected = connected);
-    }
-  }
-
-  @override
-  void dispose() {
-    _onSyncSub?.cancel();
-    _onSyncErrorSub?.cancel();
-    super.dispose();
-  }
-
-  @override
-  Widget build(BuildContext context) {
-    _onSyncSub ??= Matrix.of(context).client.onSync.stream.listen(
-          (_) => connected = true,
-        );
-    _onSyncErrorSub ??= Matrix.of(context).client.onSyncError.stream.listen(
-          (_) => connected = false,
-        );
-
-    return AnimatedContainer(
-      duration: Duration(milliseconds: 300),
-      height: _connected ? 0 : 5,
-      child: LinearProgressIndicator(),
-    );
-  }
-}