Attempting to fix IndexedDB test on IE10

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 cbdc242f6293c24ec4b322d78674819b3114fec9..3505c2e883fe4a6fed0fda16d41f16e12489ab2f 100644
--- a/tests/html/indexeddb_1_test.dart
+++ b/tests/html/indexeddb_1_test.dart
@@ -121,6 +121,12 @@ main() {
     });
   });
 
+  group('supportsDatabaseNames', () {
+    test('supported', () {
+      expect(html.window.indexedDB.supportsDatabaseNames, isTrue);
+    });
+  });
+
   group('functional', () {
     test('throws when unsupported', () {
       var expectation = idb.IdbFactory.supported ? returnsNormally : throws;