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third_party/WebKit/Source/bindings/core/v8/ScopedPersistent.h

Index: third_party/WebKit/Source/bindings/core/v8/ScopedPersistent.h
diff --git a/third_party/WebKit/Source/bindings/core/v8/ScopedPersistent.h b/third_party/WebKit/Source/bindings/core/v8/ScopedPersistent.h
index 8ffe4afff874a8a6c2f29c4d536c4a4593584411..25333d7e640018e81a364407ee05d57f084327d6 100644
--- a/third_party/WebKit/Source/bindings/core/v8/ScopedPersistent.h
+++ b/third_party/WebKit/Source/bindings/core/v8/ScopedPersistent.h
@@ -102,6 +102,12 @@ class ScopedPersistent {
 
   ALWAYS_INLINE v8::Persistent<T>& get() { return m_handle; }
 
+  template <typename S>
+  const ScopedPersistent<S>& cast() const {
+    return reinterpret_cast<const ScopedPersistent<v8::Object>&>(
+        const_cast<const ScopedPersistent<T>&>(*this));
+  }
+
  private:
   v8::Persistent<T> m_handle;
 };