Add convenience method for converting v8::PersistentBase to v8::Local

include/v8.h

Index: include/v8.h
diff --git a/include/v8.h b/include/v8.h
index 6e1db3a581f5c7ce340e3a9f6d9b4a45f06c6cff..560bfb4d00370d5edaf2ab34c4e4e8e8a7369ebf 100644
--- a/include/v8.h
+++ b/include/v8.h
@@ -509,6 +509,10 @@ template <class T> class PersistentBase {
   V8_INLINE bool IsEmpty() const { return val_ == NULL; }
   V8_INLINE void Empty() { val_ = 0; }
 
+  V8_INLINE Local<T> Get(Isolate* isolate) const {
+    return Local<T>::New(isolate, *this);
+  }
+
   template <class S>
   V8_INLINE bool operator==(const PersistentBase<S>& that) const {
     internal::Object** a = reinterpret_cast<internal::Object**>(this->val_);