Modernize the package's style.

test/priority_queue_test.dart

Index: test/priority_queue_test.dart
diff --git a/test/priority_queue_test.dart b/test/priority_queue_test.dart
index cda07489bd7f2431ee345fa0888a2c2cb8f93a90..c6966d6cda0052efd8ec0069172f1cfdde0b7f9d 100644
--- a/test/priority_queue_test.dart
+++ b/test/priority_queue_test.dart
@@ -4,9 +4,10 @@
 
 /// Tests priority queue implementations utilities.
 
-import "package:collection/priority_queue.dart";
 import "package:test/test.dart";
 
+import "package:collection/priority_queue.dart";
+
 void main() {
   testDefault();
   testInt(() => new HeapPriorityQueue<int>());
@@ -48,11 +49,9 @@ void testCustom(PriorityQueue<C> create(comparator)) {
   }
 }
 
-/**
- * Test that a queue behaves correctly.
- *
- * The elements must be in priority order, from highest to lowest.
- */
+/// Test that a queue behaves correctly.
+///
+/// The elements must be in priority order, from highest to lowest.
 void testQueue(String name, PriorityQueue create(), List elements, notElement) {
   test(name, () => testQueueBody(create, elements, notElement));
 }