Don't call dinvoke on Object methods

lib/runtime/dart/isolate.js

Index: lib/runtime/dart/isolate.js
diff --git a/lib/runtime/dart/isolate.js b/lib/runtime/dart/isolate.js
index c5a509a390c9c143146aff040f83c4d55e1418ab..f9ab35a02a1f756d6054365ad37de874191e10a2 100644
--- a/lib/runtime/dart/isolate.js
+++ b/lib/runtime/dart/isolate.js
@@ -182,7 +182,7 @@ var isolate;
       this.stackTrace = stackTrace;
     }
     toString() {
-      return 'IsolateUnhandledException: exception while handling message: ' + `${this.message} \n  ` + `${dart.dinvoke(dart.dinvoke(this.source, 'toString'), 'replaceAll', "\n", "\n  ")}\n` + 'original stack trace:\n  ' + `${this.stackTrace.toString().replaceAll("\n", "\n  ")}`;
+      return 'IsolateUnhandledException: exception while handling message: ' + `${this.message} \n  ` + `${dart.dinvoke(this.source.toString(), 'replaceAll', "\n", "\n  ")}\n` + 'original stack trace:\n  ' + `${this.stackTrace.toString().replaceAll("\n", "\n  ")}`;
     }
   }
   _IsolateUnhandledException[dart.implements] = () => [core.Exception];