[v8] Fix use of deprecated Object::Set in supervised_user_error_page

Uses the context version of Set and checks the return value (which
cannot actually fail in this case but the API requires it).

Bug: v8:7283
Change-Id: Ib22e132cee49da508a00a811f5bd67e4f5903ff2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1576570
Auto-Submit: Dan Elphick <delphick@chromium.org>
Commit-Queue: Marc Treib <treib@chromium.org>
Reviewed-by: Marc Treib <treib@chromium.org>
Cr-Commit-Position: refs/heads/master@{#653120}
diff --git a/components/supervised_user_error_page/gin_wrapper.cc b/components/supervised_user_error_page/gin_wrapper.cc
index fe4d773..bb17510 100644
--- a/components/supervised_user_error_page/gin_wrapper.cc
+++ b/components/supervised_user_error_page/gin_wrapper.cc
@@ -47,7 +47,10 @@
   if (controller.IsEmpty())
     return;
   v8::Local<v8::Object> global = context->Global();
-  global->Set(gin::StringToV8(isolate, "webRestrictions"), controller.ToV8());
+  global
+      ->Set(context, gin::StringToV8(isolate, "webRestrictions"),
+            controller.ToV8())
+      .Check();
 }
 
 void GinWrapper::Loader::OnDestruct() {