Fix rare crash when calling SetExternalResourceHEADold/5.1

This is a patch on top of the original patch that adds support for
external resources to v8::Object.

When the provided external resource pointer cannot be encoded in SMI, then we
need to allocate an object on the heap to hold it. That in turn may trigger a
garbage collection, which in turn may end up collecting the object itself.
Similarly to other methods dealing with the allocation of i::Foreign, the
insertion of a HandleScope is required.

Done-with: Lars
Task-Number: QTBUG-29127

Change-Id: I9a99998e2fbfcb8a4c1e31595344680123072c6b
Reviewed-by: Andy Shaw <[email protected]>
Reviewed-by: Lars Knoll <[email protected]>

1 files changed, 3 insertions, 1 deletions

diff --git a/src/3rdparty/v8/src/api.cc b/src/3rdparty/v8/src/api.cc
index cbb3a04..baa5b0a 100644
--- a/src/3rdparty/v8/src/api.cc
+++ b/src/3rdparty/v8/src/api.cc
@@ -4421,11 +4421,13 @@ void v8::Object::SetPointerInInternalField(int index, void* value) {
 void v8::Object::SetExternalResource(v8::Object::ExternalResource *resource) {
   i::Isolate* isolate = Utils::OpenHandle(this)->GetIsolate();
   ENTER_V8(isolate);
+  HandleScope scope;
   i::Handle<i::JSObject> obj = Utils::OpenHandle(this);
   if (CanBeEncodedAsSmi(resource)) {
     obj->SetExternalResourceObject(EncodeAsSmi(resource));
   } else {
-    obj->SetExternalResourceObject(*isolate->factory()->NewForeign(static_cast<i::Address>((void *)resource)));
+    i::Handle<i::Foreign> foreign = isolate->factory()->NewForeign(static_cast<i::Address>((void *)resource));
+    obj->SetExternalResourceObject(*foreign);
   }
   if (!obj->IsSymbol()) {
     isolate->heap()->external_string_table()->AddObject(*obj);