[Bindings] Move some private symbols from V8HiddenValue to V8PrivateProperty

third_party/WebKit/Source/bindings/core/v8/custom/V8WindowCustom.cpp

Index: third_party/WebKit/Source/bindings/core/v8/custom/V8WindowCustom.cpp
diff --git a/third_party/WebKit/Source/bindings/core/v8/custom/V8WindowCustom.cpp b/third_party/WebKit/Source/bindings/core/v8/custom/V8WindowCustom.cpp
index 4680204cd7b75a6efb403ef7fe0de72613e35fd9..8cebbf373f04eb6321eb199ef1594b10df1d98b4 100644
--- a/third_party/WebKit/Source/bindings/core/v8/custom/V8WindowCustom.cpp
+++ b/third_party/WebKit/Source/bindings/core/v8/custom/V8WindowCustom.cpp
@@ -43,6 +43,7 @@
 #include "bindings/core/v8/V8HTMLCollection.h"
 #include "bindings/core/v8/V8HiddenValue.h"
 #include "bindings/core/v8/V8Node.h"
+#include "bindings/core/v8/V8PrivateProperty.h"
 #include "core/dom/DOMArrayBuffer.h"
 #include "core/dom/MessagePort.h"
 #include "core/frame/Deprecation.h"
@@ -119,26 +120,20 @@ void V8Window::locationAttributeGetterCustom(
 void V8Window::eventAttributeGetterCustom(
     const v8::FunctionCallbackInfo<v8::Value>& info) {
   LocalDOMWindow* impl = toLocalDOMWindow(V8Window::toImpl(info.Holder()));
-  ExceptionState exceptionState(
-      info.GetIsolate(), ExceptionState::GetterContext, "Window", "event");
-  if (!BindingSecurity::shouldAllowAccessTo(currentDOMWindow(info.GetIsolate()),
-                                            impl, exceptionState)) {
+  v8::Isolate* isolate = info.GetIsolate();
+  ExceptionState exceptionState(isolate, ExceptionState::GetterContext,
+                                "Window", "event");
+  if (!BindingSecurity::shouldAllowAccessTo(currentDOMWindow(isolate), impl,
+                                            exceptionState)) {
     return;
   }
 
   LocalFrame* frame = impl->frame();
   ASSERT(frame);
-  // This is a fast path to retrieve info.Holder()->CreationContext().
-  v8::Local<v8::Context> context =
-      toV8Context(frame, DOMWrapperWorld::current(info.GetIsolate()));
-  if (context.IsEmpty())
-    return;
 
-  v8::Local<v8::Value> jsEvent = V8HiddenValue::getHiddenValue(
-      ScriptState::current(info.GetIsolate()), context->Global(),
-      V8HiddenValue::event(info.GetIsolate()));
-  if (jsEvent.IsEmpty())
-    return;
+  v8::Local<v8::Value> jsEvent =
+      V8PrivateProperty::getGlobalEvent(isolate).getOrUndefined(
+          isolate->GetCurrentContext(), info.Holder());
   v8SetReturnValue(info, jsEvent);
 }
 
@@ -146,24 +141,19 @@ void V8Window::eventAttributeSetterCustom(
     v8::Local<v8::Value> value,
     const v8::FunctionCallbackInfo<v8::Value>& info) {
   LocalDOMWindow* impl = toLocalDOMWindow(V8Window::toImpl(info.Holder()));
-  ExceptionState exceptionState(
-      info.GetIsolate(), ExceptionState::SetterContext, "Window", "event");
-  if (!BindingSecurity::shouldAllowAccessTo(currentDOMWindow(info.GetIsolate()),
-                                            impl, exceptionState)) {
+  v8::Isolate* isolate = info.GetIsolate();
+  ExceptionState exceptionState(isolate, ExceptionState::SetterContext,
+                                "Window", "event");
+  if (!BindingSecurity::shouldAllowAccessTo(currentDOMWindow(isolate), impl,
+                                            exceptionState)) {
     return;
   }
 
   LocalFrame* frame = impl->frame();
   ASSERT(frame);
-  // This is a fast path to retrieve info.Holder()->CreationContext().
-  v8::Local<v8::Context> context =
-      toV8Context(frame, DOMWrapperWorld::current(info.GetIsolate()));
-  if (context.IsEmpty())
-    return;
 
-  V8HiddenValue::setHiddenValue(ScriptState::current(info.GetIsolate()),
-                                context->Global(),
-                                V8HiddenValue::event(info.GetIsolate()), value);
+  V8PrivateProperty::getGlobalEvent(isolate).set(isolate->GetCurrentContext(),
+                                                 info.Holder(), value);

[haraken, 2017/03/29 06:35:39]

It looks like that the comment in line 158 (before this CL) is saying that we
should set info.Holder()->CreationContext(). Is the new code correct?

[Yuki, 2017/03/29 06:46:41]

Yes, the new code is more correct than before.

We're not creating any new object, so we don't need the DOM object's creation
context (= relevant realm for the context object).  |value| is the object to be
set, but it's given from author script as an argument.  We're not creating it.

A possible exception object is an exception, we could create and throw an
exception, but it should be created in the current context.  (So, the old
implementation is wrong on this point.)

Plus, v8:Private:{Get,Set} must not invoke any author script.

 }
 
 void V8Window::frameElementAttributeGetterCustom(