| Index: third_party/WebKit/Source/core/streams/UnderlyingSourceBase.idl | 
| diff --git a/third_party/WebKit/Source/core/streams/UnderlyingSourceBase.idl b/third_party/WebKit/Source/core/streams/UnderlyingSourceBase.idl | 
| index 0c0486fddbfea1ceca07201d99870e01d88598e2..ad9e37461848ad593dbd5d6252733a168086293c 100644 | 
| --- a/third_party/WebKit/Source/core/streams/UnderlyingSourceBase.idl | 
| +++ b/third_party/WebKit/Source/core/streams/UnderlyingSourceBase.idl | 
| @@ -7,7 +7,12 @@ | 
| // UnderlyingSourceBase, and a JavaScript object can then be generated | 
| // automatically for use in initializing a ReadableStream. | 
|  | 
| -[NoInterfaceObject, GarbageCollected, DependentLifetime] | 
| +[ | 
| +    ActiveScriptWrappable, | 
| +    DependentLifetime, | 
| +    GarbageCollected, | 
| +    NoInterfaceObject, | 
| +] | 
| interface UnderlyingSourceBase { | 
| [CallWith=ScriptState, ImplementedAs=startWrapper] Promise<void> start(any stream); | 
| [CallWith=ScriptState] Promise<void> pull(); | 
|  |