7000847: add type tag to v8::External calls in callback and osr_converter

The v8::External API now requires an EmbedderPointerTypeTag parameter
for both New() and Value() methods to improve V8 sandbox type safety.

Updated calls in:
- callback.cc: TranslatorHolder constructor and CallTranslator
- osr_converter.cc: OffscreenSharedTextureValue converter

Ref: https://chromium-review.googlesource.com/c/v8/v8/+/7000847

shell/common/gin_converters/osr_converter.cc

@@ -87,10 +87,12 @@ v8::Local<v8::Value> Converter<electron::OffscreenSharedTextureValue>::ToV8(
   // GC collects the object.
   auto* monitor = new OffscreenReleaseHolderMonitor(val.releaser_holder);
 
-  auto releaserHolder = v8::External::New(isolate, monitor);
+  auto releaserHolder =
+      v8::External::New(isolate, monitor, v8::kExternalPointerTypeTagDefault);
   auto releaserFunc = [](const v8::FunctionCallbackInfo<v8::Value>& info) {
     auto* mon = static_cast<OffscreenReleaseHolderMonitor*>(
-        info.Data().As<v8::External>()->Value());
+        info.Data().As<v8::External>()->Value(
+            v8::kExternalPointerTypeTagDefault));
     // Release the shared texture, so that future frames can be generated.
     mon->ReleaseTexture();
     // Release the monitor happens at GC, don't release here.

shell/common/gin_helper/callback.cc

@@ -14,7 +14,10 @@ namespace {
 
 struct TranslatorHolder {
   explicit TranslatorHolder(v8::Isolate* isolate)
-      : handle(isolate, v8::External::New(isolate, this)) {
+      : handle(isolate,
+               v8::External::New(isolate,
+                                 this,
+                                 v8::kExternalPointerTypeTagDefault)) {
     handle.SetWeak(this, &GC, v8::WeakCallbackType::kParameter);
   }
   ~TranslatorHolder() {
@@ -57,7 +60,8 @@ void CallTranslator(v8::Local<v8::External> external,
     }
   }
 
-  auto* holder = static_cast<TranslatorHolder*>(external->Value());
+  auto* holder = static_cast<TranslatorHolder*>(
+      external->Value(v8::kExternalPointerTypeTagDefault));
   holder->translator.Run(args);
 
   // Free immediately for one-time callback.