WIP bindings: Add support for the record<K,V> WebIDL type.

third_party/WebKit/Source/bindings/tests/results/core/LongCallbackFunction.h

Index: third_party/WebKit/Source/bindings/tests/results/core/LongCallbackFunction.h
diff --git a/third_party/WebKit/Source/bindings/tests/results/core/LongCallbackFunction.h b/third_party/WebKit/Source/bindings/tests/results/core/LongCallbackFunction.h
index ecf82d0834758b86422bd501f7a7384b8697cdf9..79d48a517d8128244f4c88616a027280a55fe6bb 100644
--- a/third_party/WebKit/Source/bindings/tests/results/core/LongCallbackFunction.h
+++ b/third_party/WebKit/Source/bindings/tests/results/core/LongCallbackFunction.h
@@ -13,6 +13,7 @@
 #ifndef LongCallbackFunction_h
 #define LongCallbackFunction_h
 
+#include "bindings/core/v8/NativeValueTraits.h"
 #include "bindings/core/v8/ScriptWrappable.h"
 #include "bindings/core/v8/TraceWrapperV8Reference.h"
 #include "core/CoreExport.h"
@@ -45,6 +46,12 @@ class CORE_EXPORT LongCallbackFunction final : public GarbageCollectedFinalized<
   TraceWrapperV8Reference<v8::Function> m_callback;
 };
 
+template <>
+struct NativeValueTraits<LongCallbackFunction> {
+  using ImplType = LongCallbackFunction;
+  CORE_EXPORT static LongCallbackFunction* nativeValue(v8::Isolate*, v8::Local<v8::Value>, ExceptionState&);
+};
+
 }  // namespace blink
 
 #endif  // LongCallbackFunction_h