| Index: Source/core/frame/UseCounter.h | 
| diff --git a/Source/core/frame/UseCounter.h b/Source/core/frame/UseCounter.h | 
| index 849c3c6666c6ed9233a87873f1bb1862dd6aa26c..b12f83f87d385c99b3b81e97667f0c475ffc0506 100644 | 
| --- a/Source/core/frame/UseCounter.h | 
| +++ b/Source/core/frame/UseCounter.h | 
| @@ -841,6 +841,7 @@ public: | 
| V8Window_Confirm_Method = 951, | 
| V8Window_Prompt_Method = 952, | 
| V8Window_Print_Method = 953, | 
| +        V8Window_RequestIdleCallback_Method = 954, | 
|  | 
| // Add new features immediately above this line. Don't change assigned | 
| // numbers of any item, and don't reuse removed slots. | 
|  |