Use v8::Context::NewRemoteContext in RemoteWindowProxy.

third_party/WebKit/Source/bindings/core/v8/DOMDataStore.h

Index: third_party/WebKit/Source/bindings/core/v8/DOMDataStore.h
diff --git a/third_party/WebKit/Source/bindings/core/v8/DOMDataStore.h b/third_party/WebKit/Source/bindings/core/v8/DOMDataStore.h
index 03d903065415b8d46156e68f9e01e0d5b8b46332..3cd3c86a01306642442145928bcf6e7d4b7f32cc 100644
--- a/third_party/WebKit/Source/bindings/core/v8/DOMDataStore.h
+++ b/third_party/WebKit/Source/bindings/core/v8/DOMDataStore.h
@@ -138,6 +138,8 @@ class DOMDataStore {
   }
 
  private:
+  friend class RemoteWindowProxy;

[Yuki, 2017/03/23 02:58:29]

I think that we don't have a strong reason to make |set| private:.  |get| is
already public:.

I'd prefer making |set| public: rather than making WindowProxy a friend class.

[dcheng, 2017/03/23 06:03:06]

OK, I was thinking we didn't want to expose this more widely, but if you're OK
with exposing it publicly, I guess that's fine.

+
   WARN_UNUSED_RESULT bool set(v8::Isolate* isolate,
                               ScriptWrappable* object,
                               const WrapperTypeInfo* wrapperTypeInfo,