[Isolates] Fix auto extraction of isolate from heap objects in handle constructor.

src/handles-inl.h

Index: src/handles-inl.h
diff --git a/src/handles-inl.h b/src/handles-inl.h
index 6e7c3d972434f16fb7ce410824e22112f1f8649e..cfe34f1230a899497bd622670300dc51e4541964 100644
--- a/src/handles-inl.h
+++ b/src/handles-inl.h
@@ -37,15 +37,18 @@
 namespace v8 {
 namespace internal {
 
-template<class T>
-Handle<T>::Handle(T* obj) {
-  ASSERT(!obj->IsFailure());
-  location_ = HandleScope::CreateHandle(obj, Isolate::Current());
+inline Isolate* GetIsolateForHandle(Object* obj) {
+  return Isolate::Current();
+}
+
+inline Isolate* GetIsolateForHandle(HeapObject* obj) {
+  return obj->GetIsolate();
 }
 
 template<class T>
-Handle<T>::Handle(HeapObject* obj) {
-  location_ = HandleScope::CreateHandle<T>(obj, obj->GetIsolate());
+Handle<T>::Handle(T* obj) {
+  ASSERT(!obj->IsFailure());
+  location_ = HandleScope::CreateHandle(obj, GetIsolateForHandle(obj));
 }