[Bindings] Move and remove some private symbols from V8HiddenValue

third_party/WebKit/Source/modules/fetch/Request.cpp

Index: third_party/WebKit/Source/modules/fetch/Request.cpp
diff --git a/third_party/WebKit/Source/modules/fetch/Request.cpp b/third_party/WebKit/Source/modules/fetch/Request.cpp
index 666857c4d2cfa63055052f5c2b60276572164c31..85c12274036f9701af3d3772d7f4955aabeb909b 100644
--- a/third_party/WebKit/Source/modules/fetch/Request.cpp
+++ b/third_party/WebKit/Source/modules/fetch/Request.cpp
@@ -5,6 +5,7 @@
 #include "modules/fetch/Request.h"
 
 #include "bindings/core/v8/Dictionary.h"
+#include "bindings/core/v8/V8PrivateProperty.h"
 #include "core/dom/Document.h"
 #include "core/dom/ExecutionContext.h"
 #include "core/loader/ThreadableLoader.h"
@@ -728,9 +729,8 @@ void Request::refreshBody(ScriptState* scriptState) {
     return;
   }
   DCHECK(request->IsObject());
-  V8HiddenValue::setHiddenValue(
-      scriptState, request.As<v8::Object>(),
-      V8HiddenValue::internalBodyBuffer(scriptState->isolate()), bodyBuffer);
+  V8PrivateProperty::getInternalBodyBuffer(scriptState->isolate())
+      .set(request.As<v8::Object>(), bodyBuffer);

[haraken, 2017/03/30 14:04:45]

This private property is set but never get.

Is it probably used to keep alive the body buffer? If that is the case, we
should replace it with the wrapper tracing. You don't need to address it in this
CL though.

[peria, 2017/04/04 05:48:58]

Those private properties you commented on seem to be used
to keep other wrappers alive.
I'll do it in another CL.

 }
 
 DEFINE_TRACE(Request) {