Fix a couple lints
diff --git a/lib/src/typed_queue.dart b/lib/src/typed_queue.dart
index df91e35..8d83944 100644
--- a/lib/src/typed_queue.dart
+++ b/lib/src/typed_queue.dart
@@ -647,7 +647,7 @@
   assert(number > 0);
   number = (number << 1) - 1;
   for (;;) {
-    int nextNumber = number & (number - 1);
+    var nextNumber = number & (number - 1);
     if (nextNumber == 0) return number;
     number = nextNumber;
   }
diff --git a/test/queue_test.dart b/test/queue_test.dart
index 6b6daf9..82d96f6 100644
--- a/test/queue_test.dart
+++ b/test/queue_test.dart
@@ -264,7 +264,7 @@
 
 /// Runs [callback] in multiple tests, all with queues containing numbers from
 /// one through 15 in various different internal states.
-void forEachInternalRepresentation(void callback(Uint8Queue queue)) {
+void forEachInternalRepresentation(void Function(Uint8Queue queue) callback) {
   // Test with a queue whose internal table has plenty of room.
   group("for a queue that's below capacity", () {
     // Test with a queue whose elements are in one contiguous block, so `_head <