msglist: Exclude muted users from typing-status text

Following web:
  zulip#1429 (review)

Author: chrisbobbe

lib/widgets/message_list.dart

@@ -947,12 +947,15 @@ class _TypingStatusWidgetState extends State<TypingStatusWidget> with PerAccount
     final zulipLocalizations = ZulipLocalizations.of(context);
     final typistIds = model!.typistIdsInNarrow(narrow);
     if (typistIds == null) return const SizedBox();
-    final text = switch (typistIds.length) {
+    final filteredTypistIds = typistIds
+      .whereNot((userId) => store.isUserMuted(userId));
+    if (filteredTypistIds.isEmpty) return const SizedBox();
+    final text = switch (filteredTypistIds.length) {
       1 => zulipLocalizations.onePersonTyping(
-             store.userDisplayName(typistIds.first)),
+             store.userDisplayName(filteredTypistIds.first)),
       2 => zulipLocalizations.twoPeopleTyping(
-             store.userDisplayName(typistIds.first),
-             store.userDisplayName(typistIds.last)),
+             store.userDisplayName(filteredTypistIds.first),
+             store.userDisplayName(filteredTypistIds.last)),
       _ => zulipLocalizations.manyPeopleTyping,
     };
 

test/widgets/message_list_test.dart

@@ -756,9 +756,19 @@ void main() {
         await checkTyping(tester,
           eg.typingEvent(narrow, TypingOp.stop, eg.otherUser.userId),
           expected: 'Third User and Fourth User are typing…');
+        await store.setMutedUsers([eg.thirdUser.userId]);
+        await tester.pump();
+        check(tester.widget<Text>(finder)).data.equals('Fourth User is typing…');
         // Verify that typing indicators expire after a set duration.
         await tester.pump(const Duration(seconds: 15));
         check(finder.evaluate()).isEmpty();
+        // Muted user starts typing again; nothing is shown.
+        await store.handleEvent(
+          eg.typingEvent(narrow, TypingOp.start, eg.thirdUser.userId));
+        await tester.pump();
+        check(finder.evaluate()).isEmpty();
+        await tester.pump(const Duration(seconds: 15));
+        check(finder.evaluate()).isEmpty();
       });
     }