Merge pull request #151 from srawlins/catcherror

Return valid type from Future.catchError.
diff --git a/lib/src/usage_impl.dart b/lib/src/usage_impl.dart
index 73acc24..c774c6f 100644
--- a/lib/src/usage_impl.dart
+++ b/lib/src/usage_impl.dart
@@ -198,8 +198,8 @@
   Stream<Map<String, dynamic>> get onSend => _sendController.stream;
 
   @override
-  Future waitForLastPing({Duration? timeout}) {
-    Future f = Future.wait(_futures).catchError((e) => null);
+  Future<List<dynamic>> waitForLastPing({Duration? timeout}) {
+    var f = Future.wait(_futures).catchError((e) => []);
 
     if (timeout != null) {
       f = f.timeout(timeout, onTimeout: () => []);