refactor: Remove unnecessary builder widget

lib/pages/chat/chat_event_list.dart

@@ -23,9 +23,18 @@ class ChatEventList extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
+    final timeline = controller.timeline;
+    if (timeline == null) {
+      return const Center(
+        child: CircularProgressIndicator.adaptive(
+          strokeWidth: 2,
+        ),
+      );
+    }
+
     final horizontalPadding = FluffyThemes.isColumnMode(context) ? 8.0 : 0.0;
 
-    final events = controller.timeline!.events.filterByVisibleInGui();
+    final events = timeline.events.filterByVisibleInGui();
     final animateInEventIndex = controller.animateInEventIndex;
 
     // create a map of eventId --> index to greatly improve performance of
@@ -55,12 +64,12 @@ class ChatEventList extends StatelessWidget {
           (BuildContext context, int i) {
             // Footer to display typing indicator and read receipts:
             if (i == 0) {
-              if (controller.timeline!.isRequestingFuture) {
+              if (timeline.isRequestingFuture) {
                 return const Center(
                   child: CircularProgressIndicator.adaptive(strokeWidth: 2),
                 );
               }
-              if (controller.timeline!.canRequestFuture) {
+              if (timeline.canRequestFuture) {
                 return Center(
                   child: IconButton(
                     onPressed: controller.requestFuture,
@@ -79,12 +88,12 @@ class ChatEventList extends StatelessWidget {
 
             // Request history button or progress indicator:
             if (i == events.length + 1) {
-              if (controller.timeline!.isRequestingHistory) {
+              if (timeline.isRequestingHistory) {
                 return const Center(
                   child: CircularProgressIndicator.adaptive(strokeWidth: 2),
                 );
               }
-              if (controller.timeline!.canRequestHistory) {
+              if (timeline.canRequestHistory) {
                 return Builder(
                   builder: (context) {
                     WidgetsBinding.instance
@@ -105,8 +114,8 @@ class ChatEventList extends StatelessWidget {
             // The message at this index:
             final event = events[i];
             final animateIn = animateInEventIndex != null &&
-                controller.timeline!.events.length > animateInEventIndex &&
-                event == controller.timeline!.events[animateInEventIndex];
+                timeline.events.length > animateInEventIndex &&
+                event == timeline.events[animateInEventIndex];
 
             return AutoScrollTag(
               key: ValueKey(event.eventId),
@@ -137,7 +146,7 @@ class ChatEventList extends StatelessWidget {
                 longPressSelect: controller.selectedEvents.isNotEmpty,
                 selected: controller.selectedEvents
                     .any((e) => e.eventId == event.eventId),
-                timeline: controller.timeline!,
+                timeline: timeline,
                 displayReadMarker:
                     i > 0 && controller.readMarkerEventId == event.eventId,
                 nextEvent: i + 1 < events.length ? events[i + 1] : null,

lib/pages/chat/chat_view.dart

@@ -287,20 +287,7 @@ class ChatView extends StatelessWidget {
                           Expanded(
                             child: GestureDetector(
                               onTap: controller.clearSingleSelectedEvent,
-                              child: Builder(
-                                builder: (context) {
-                                  if (controller.timeline == null) {
-                                    return const Center(
-                                      child: CircularProgressIndicator.adaptive(
-                                        strokeWidth: 2,
-                                      ),
-                                    );
-                                  }
-                                  return ChatEventList(
-                                    controller: controller,
-                                  );
-                                },
-                              ),
+                              child: ChatEventList(controller: controller),
                             ),
                           ),
                           if (controller.room.canSendDefaultMessages &&