perf(ffi/v8): kNonMasking on native instances - 773ms benchmark

Use kNonMasking interceptor on native object instances only (not class
or bridge host objects). This allows V8 to find prototype properties
without calling the interceptor, giving a 40% speedup.

Benchmark: 773ms (was 1250ms)
Tests: 713 total, 7 failures remaining (superclass/instanceof edge cases)

Also fix readonly property test expectations to accept V8's native
error message with kNonMasking.

Author: DjDeveloperr

NativeScript/ffi/shared/bridge/HostObjects.mm

@@ -1762,7 +1762,7 @@ Value makeNativeObjectValue(Runtime& runtime,
     bridge->forgetRoundTripValue(runtime, object);
   }
 
-  Object result = Object::createFromHostObject(
+  Object result = Object::createNativeInstanceHostObject(
       runtime,
       std::make_shared<NativeApiObjectHostObject>(bridge, object, ownsObject));
   Value prototypeValue = Value::undefined();

NativeScript/ffi/v8/NativeApiV8HostObjects.mm

@@ -52,6 +52,34 @@ void emplace(size_t index, Value&& value) {
   if (state->hostObjectTemplate.IsEmpty()) {
     v8::Local<v8::ObjectTemplate> objectTemplate = v8::ObjectTemplate::New(runtime.isolate());
     objectTemplate->SetInternalFieldCount(1);
+    // toString must be own property to override Object.prototype.toString
+    // when using kNonMasking interceptor.
+    objectTemplate->Set(
+        makeV8String(runtime.isolate(), "toString"),
+        v8::FunctionTemplate::New(runtime.isolate(),
+            [](const v8::FunctionCallbackInfo<v8::Value>& info) {
+              v8::Local<v8::Object> self = info.This();
+              if (self.IsEmpty() || self->InternalFieldCount() < 1) return;
+              auto* holder = static_cast<HostObjectHolder*>(
+                  self->GetAlignedPointerFromInternalField(0));
+              if (holder == nullptr || holder->hostObject == nullptr) return;
+              Runtime rt(holder->state);
+              try {
+                Value toStr = holder->hostObject->get(rt, PropNameID("toString"));
+                if (!toStr.isUndefined()) {
+                  v8::Local<v8::Value> v8Val = toStr.local(rt);
+                  if (v8Val->IsFunction()) {
+                    v8::Local<v8::Value> result;
+                    if (v8Val.As<v8::Function>()->Call(rt.context(), self, 0, nullptr)
+                            .ToLocal(&result)) {
+                      info.GetReturnValue().Set(result);
+                      return;
+                    }
+                  }
+                }
+              } catch (...) {}
+            }),
+        v8::DontEnum);
     objectTemplate->SetHandler(v8::NamedPropertyHandlerConfiguration(
         [](v8::Local<v8::Name> property,
            const v8::PropertyCallbackInfo<v8::Value>& info) -> v8::Intercepted {

test/runtime/runner/app/tests/Inheritance/InheritanceTests.js

@@ -307,7 +307,7 @@ describe(module.id, function () {
         UNUSED(object.baseProtocolProperty2Optional);
         object.baseProperty = 0;
         UNUSED(object.baseProperty);
-        expect(() => object.baseReadOnlyProperty = 0).toThrowError("Attempted to assign to readonly property.");
+        expect(() => object.baseReadOnlyProperty = 0).toThrowError(/Attempted to assign to readonly property|Cannot set property.*which has only a getter/);
         UNUSED(object.baseReadOnlyProperty);
         object.baseCategoryProtocolProperty1 = 0;
         UNUSED(object.baseCategoryProtocolProperty1);

test/runtime/runner/app/tests/MethodCallsTests.js

@@ -1000,7 +1000,7 @@ describe(module.id, function () {
     it('Derived_DerivedPropertyReadOnly', function () {
         "use strict";
         var instance = TNSDerivedInterface.alloc().init();
-        expect(() => instance.derivedPropertyReadOnly = 1).toThrowError(/Attempted to assign to readonly property/);
+        expect(() => instance.derivedPropertyReadOnly = 1).toThrowError(/Attempted to assign to readonly property|Cannot set property.*which has only a getter/);
         UNUSED(instance.derivedPropertyReadOnly);
 
         var actual = TNSGetOutput();