Add more error handling to unawaited callsites (#184526)

Part of flutter/flutter#181513

Author: victorsanni

packages/flutter/lib/src/material/calendar_date_picker.dart

@@ -244,7 +244,11 @@ class _CalendarDatePickerState extends State<CalendarDatePicker> {
   // Auxiliary method for handling the difference between platforms
   void _announce(String message) {
     if (MediaQuery.maybeSupportsAnnounceOf(context) ?? false) {
-      SemanticsService.sendAnnouncement(View.of(context), message, Directionality.of(context));
+      SemanticsService.sendAnnouncement(
+        View.of(context),
+        message,
+        Directionality.of(context),
+      ).catchError(_reportAnnouncementError);
     } else {
       // If SemanticsService.sendAnnouncement is not supported,
       // we use live region to achieve the announcement effect instead.
@@ -328,7 +332,7 @@ class _CalendarDatePickerState extends State<CalendarDatePicker> {
             View.of(context),
             '${_localizations.selectedDateLabel} ${widget.calendarDelegate.formatFullDate(_selectedDate!, _localizations)}$semanticLabelSuffix',
             _textDirection,
-          );
+          ).catchError(_reportAnnouncementError);
         case TargetPlatform.android:
         case TargetPlatform.iOS:
         case TargetPlatform.fuchsia:
@@ -675,7 +679,11 @@ class _MonthPickerState extends State<_MonthPicker> {
   // Auxiliary method for handling the difference between platforms
   void _announce(String message) {
     if (MediaQuery.maybeSupportsAnnounceOf(context) ?? false) {
-      SemanticsService.sendAnnouncement(View.of(context), message, Directionality.of(context));
+      SemanticsService.sendAnnouncement(
+        View.of(context),
+        message,
+        Directionality.of(context),
+      ).catchError(_reportAnnouncementError);
     } else {
       // If SemanticsService.sendAnnouncement is not supported,
       // we use live region to achieve the announcement effect instead.
@@ -1635,3 +1643,14 @@ class _YearPickerGridDelegate extends SliverGridDelegate {
   @override
   bool shouldRelayout(_YearPickerGridDelegate oldDelegate) => false;
 }
+
+void _reportAnnouncementError(Object exception, StackTrace stack) {
+  FlutterError.reportError(
+    FlutterErrorDetails(
+      exception: exception,
+      stack: stack,
+      library: 'material library',
+      context: ErrorDescription('while sending semantics announcement'),
+    ),
+  );
+}

packages/flutter/lib/src/material/expansion_tile.dart

@@ -557,15 +557,39 @@ class _ExpansionTileState extends State<ExpansionTile> {
       // semantic announcements on iOS. https://github.com/flutter/flutter/issues/122101.
       _timer?.cancel();
       _timer = Timer(const Duration(seconds: 1), () {
-        SemanticsService.sendAnnouncement(View.of(context), stateHint, textDirection);
+        SemanticsService.sendAnnouncement(View.of(context), stateHint, textDirection).catchError((
+          Object exception,
+          StackTrace stack,
+        ) {
+          FlutterError.reportError(
+            FlutterErrorDetails(
+              exception: exception,
+              stack: stack,
+              library: 'material library',
+              context: ErrorDescription('while sending semantics announcement'),
+            ),
+          );
+        });
         _timer?.cancel();
         _timer = null;
       });
     }
     // SemanticsService.sendAnnouncement is deprecated on android.
     // We use live region to achieve the announcement effect instead.
     else if (defaultTargetPlatform != TargetPlatform.android) {
-      SemanticsService.sendAnnouncement(View.of(context), stateHint, textDirection);
+      SemanticsService.sendAnnouncement(View.of(context), stateHint, textDirection).catchError((
+        Object exception,
+        StackTrace stack,
+      ) {
+        FlutterError.reportError(
+          FlutterErrorDetails(
+            exception: exception,
+            stack: stack,
+            library: 'material library',
+            context: ErrorDescription('while sending semantics announcement'),
+          ),
+        );
+      });
     }
     widget.onExpansionChanged?.call(_tileController.isExpanded);
   }