Reflect recent spec changes to V8 Extra ReadableStream impl

third_party/WebKit/Source/core/streams/UnderlyingSourceBase.cpp

Index: third_party/WebKit/Source/core/streams/UnderlyingSourceBase.cpp
diff --git a/third_party/WebKit/Source/core/streams/UnderlyingSourceBase.cpp b/third_party/WebKit/Source/core/streams/UnderlyingSourceBase.cpp
index b63fe960860111b84c995e15bd4ffeda51ab5471..056b9a477803046bba338e960e2e99e95793f931 100644
--- a/third_party/WebKit/Source/core/streams/UnderlyingSourceBase.cpp
+++ b/third_party/WebKit/Source/core/streams/UnderlyingSourceBase.cpp
@@ -12,15 +12,12 @@
 
 namespace blink {
 
-ScriptPromise UnderlyingSourceBase::startWrapper(ScriptState* scriptState, ScriptValue stream)
+ScriptPromise UnderlyingSourceBase::startWrapper(ScriptState* scriptState, ScriptValue jsController)
 {
     // Cannot call start twice (e.g., cannot use the same UnderlyingSourceBase to construct multiple streams)
     ASSERT(!m_controller);
 
-    // In ReadableStream.js, we special-case externally-controlled streams by having them pass themselves to start
-    // as the first argument. This allows us to create a ReadableStreamController.
-
-    m_controller = new ReadableStreamController(stream);
+    m_controller = new ReadableStreamController(jsController);
 
     return start(scriptState);
 }