Make the "sticky error" an Error instead of a String.

runtime/vm/longjump.cc

 // Copyright (c) 2011, 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.
 
 #include "vm/longjump.h"
 
 #include "include/dart_api.h"
 
 #include "vm/dart_api_impl.h"
 #include "vm/isolate.h"
 #include "vm/object.h"
 #include "vm/object_store.h"
 #include "vm/os.h"
 
 namespace dart {
 
 jmp_buf* LongJump::Set() {
   top_ = Isolate::Current()->top_resource();
   return &environment_;
 }
 
 
-void LongJump::Jump(int value, const char* msg) {
+void LongJump::Jump(int value, const Error& error) {
   // A zero is the default return value from setting up a LongJump using Set.
   ASSERT(value != 0);
 
   Isolate* isolate = Isolate::Current();
 
-  // Remember the message in the sticky error message of this isolate.
-  const String& error = String::Handle(String::New(msg));
+  // Remember the error in the sticky error of this isolate.
   isolate->object_store()->set_sticky_error(error);
 
   // Destruct all the active StackResource objects.
   StackResource* current_resource = isolate->top_resource();
   while (current_resource != top_) {
     current_resource->~StackResource();
     current_resource = isolate->top_resource();
   }
   longjmp(environment_, value);
   UNREACHABLE();
 }
 
 }  // namespace dart