Fixing some indexed_db tests.

tests/html/indexeddb_1_test.dart

Index: tests/html/indexeddb_1_test.dart
diff --git a/tests/html/indexeddb_1_test.dart b/tests/html/indexeddb_1_test.dart
index 92eef204f428a613cb0a6985cb627a6cafdf4f06..eac993f91b808e0258cb63ded78bf6686172c3f0 100644
--- a/tests/html/indexeddb_1_test.dart
+++ b/tests/html/indexeddb_1_test.dart
@@ -39,8 +39,9 @@ testReadWrite(key, value, matcher,
   step1() {
     var transaction = db.transaction([storeName], 'readwrite');
     var request = transaction.objectStore(storeName).put(value, key);
-    request.onSuccess.listen(expectAsync1(step2));
     request.onError.listen(fail);
+
+    transaction.onComplete.listen(expectAsync1(step2));
   }
 
   initDb(e) {
@@ -115,8 +116,9 @@ testReadWriteTyped(key, value, matcher,
   step1() {
     idb.Transaction transaction = db.transaction([storeName], 'readwrite');
     idb.Request request = transaction.objectStore(storeName).put(value, key);
-    request.onSuccess.listen(expectAsync1(step2));
     request.onError.listen(fail);
+
+    transaction.onComplete.listen(expectAsync1(step2));
   }
 
   initDb(e) {