| Index: runtime/vm/isolate.h | 
| diff --git a/runtime/vm/isolate.h b/runtime/vm/isolate.h | 
| index 128f7e22cafa3853a9ec070fc7c0843e1df44b35..f42247e34824fbaa4c40cd7069c7e777c0e1e2a1 100644 | 
| --- a/runtime/vm/isolate.h | 
| +++ b/runtime/vm/isolate.h | 
| @@ -512,7 +512,7 @@ class SwitchIsolateScope { | 
|  | 
| class IsolateSpawnState { | 
| public: | 
| -  IsolateSpawnState(const Function& func, const Function& callback_func); | 
| +  explicit IsolateSpawnState(const Function& func); | 
| explicit IsolateSpawnState(const char* script_url); | 
| ~IsolateSpawnState(); | 
|  | 
| @@ -522,6 +522,7 @@ class IsolateSpawnState { | 
| char* library_url() const { return library_url_; } | 
| char* function_name() const { return function_name_; } | 
| char* exception_callback_name() const { return exception_callback_name_; } | 
| +  bool is_spawn_uri() const { return library_url_ == NULL; } | 
|  | 
| RawObject* ResolveFunction(); | 
| void Cleanup(); | 
|  |