Use custom app bar for call windows

lib/ui/widgets/tablet_mode/calls/call_window_widget.dart

@@ -1,20 +1,25 @@
 import 'package:comunic/ui/screens/call_screen.dart';
+import 'package:comunic/ui/widgets/custom_app_bar_size.dart';
 import 'package:comunic/ui/widgets/tablet_mode/calls/calls_area.dart';
+import 'package:comunic/utils/intl_utils.dart';
 import 'package:flutter/material.dart';
 
 /// Call window widget
 ///
 /// @author Pierre HUBERT
 
-const _WindowSize = Size(500, 200);
+const _WindowSize = Size(450, 200);
 
 class CallWindowWidget extends StatefulWidget {
   final int convID;
+  final void Function() onClose;
 
   const CallWindowWidget({
     Key key,
-    this.convID,
+    @required this.convID,
+    @required this.onClose,
   })  : assert(convID != null),
+        assert(onClose != null),
         super(key: key);
 
   @override
@@ -43,6 +48,19 @@ class _CallWindowWidgetState extends State<CallWindowWidget> {
       child: Draggable(
         child: Card(
           child: CallScreen(
+            buildCustomAppBar: (convName) => AppBarWrapper(
+                height: 30,
+                appBar: AppBar(
+                  backgroundColor: Colors.black,
+                  title: Text(convName == null ? tr("Loading...") : convName),
+                  actions: <Widget>[
+                    IconButton(
+                      iconSize: 16,
+                      icon: Icon(Icons.close),
+                      onPressed: widget.onClose,
+                    )
+                  ],
+                )),
             convID: widget.convID,
             floatingButtons: false,
           ),

lib/ui/widgets/tablet_mode/calls/calls_area.dart

@@ -19,8 +19,13 @@ class CallsAreaState extends State<CallsArea> {
   Widget build(BuildContext context) {
     return Stack(
       children: _openCalls
-          .map((convID, key) =>
-              MapEntry(convID, CallWindowWidget(key: key, convID: convID)))
+          .map((convID, key) => MapEntry(
+              convID,
+              CallWindowWidget(
+                key: key,
+                convID: convID,
+                onClose: () => closeCall(convID),
+              )))
           .values
           .toList(),
     );
@@ -34,4 +39,10 @@ class CallsAreaState extends State<CallsArea> {
       });
     }
   }
+
+  /// Close a call
+  void closeCall(int convID) {
+    if (_openCalls.containsKey(convID))
+      setState(() => _openCalls.remove(convID));
+  }
 }