fix #30094, assert should work with a function

pkg/dev_compiler/tool/input_sdk/private/ddc_runtime/errors.dart

Index: pkg/dev_compiler/tool/input_sdk/private/ddc_runtime/errors.dart
diff --git a/pkg/dev_compiler/tool/input_sdk/private/ddc_runtime/errors.dart b/pkg/dev_compiler/tool/input_sdk/private/ddc_runtime/errors.dart
index 7d57650ee0c7956058148a1438f6931f7d9d93b9..79a01db5182789cb45778ee0f1f784b27a6b37ee 100644
--- a/pkg/dev_compiler/tool/input_sdk/private/ddc_runtime/errors.dart
+++ b/pkg/dev_compiler/tool/input_sdk/private/ddc_runtime/errors.dart
@@ -73,11 +73,10 @@ throwUnimplementedError(String message) {
   throw new UnimplementedError(message);
 }
 
-throwAssertionError([String message()]) {
+throwAssertionError(messageFn()) {
   if (JS('bool', 'dart.__trapRuntimeErrors')) JS('', 'debugger');
-  throw message != null
-      ? new AssertionErrorWithMessage(message())
-      : new AssertionError();
+  var message = messageFn != null ? messageFn() : null;
+  throw new AssertionErrorImpl(message);
 }
 
 throwCyclicInitializationError([String message]) {