Fix for issue 11680

runtime/lib/errors_patch.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 patch class Error {
   /* patch */ static String _objectToString(Object object) {
     return Object._toString(object);
   }
 
-  // TODO(11680): implement stackTrace on Error.
-  /* patch */ StackTrace get stackTrace => null;
+  /* patch */ StackTrace get stackTrace => _stackTrace;
+
+  StackTrace _stackTrace;
 }
 
 patch class NoSuchMethodError {
   // The compiler emits a call to _throwNew when it cannot resolve a static
   // method at compile time. The receiver is actually the literal class of the
   // unresolved method.
   static void _throwNew(Object receiver,
                         String memberName,
                         int invocation_type,
                         List arguments,
@@ skipping 154 matching lines @@
     return msg_buf.toString();
   }
 }
 
 class _FiftyThreeBitOverflowError extends Error {
   final Object _value;
 
   _FiftyThreeBitOverflowError(this._value);
   String toString() => "53-bit Overflow: $_value";
 }