Add special case templates to handle Global/WindowEventHandlers

tests/compiler/dart2js/analyze_api_test.dart

Index: tests/compiler/dart2js/analyze_api_test.dart
diff --git a/tests/compiler/dart2js/analyze_api_test.dart b/tests/compiler/dart2js/analyze_api_test.dart
index f76fb9426b2f6d23d3f102351ef3eef1121993be..de48a2ec6e6e4ff435947050b599aa850888ec13 100644
--- a/tests/compiler/dart2js/analyze_api_test.dart
+++ b/tests/compiler/dart2js/analyze_api_test.dart
@@ -20,10 +20,6 @@ import "package:async_helper/async_helper.dart";
 // TODO(johnniwinther): Support canonical URIs as keys and message kinds as
 // values.
 const Map<String, List<String>> WHITE_LIST = const {
-  'html_dart2js.dart': const [
-      // Issue 15954:
-      "'GlobalEventHandlers' is not assignable to 'EventTarget'",
-      "'WindowEventHandlers' is not assignable to 'EventTarget'"]
 };
 
 void main() {