binidngs: Make callInternalFunction return MaybeLocal

Source/bindings/core/v8/NPV8Object.cpp

Index: Source/bindings/core/v8/NPV8Object.cpp
diff --git a/Source/bindings/core/v8/NPV8Object.cpp b/Source/bindings/core/v8/NPV8Object.cpp
index 0c65fd6829f766cfadb09d293c8509e646e1f128..45b2d7a5f630c4bab055fb0fb585649b5b60c214 100644
--- a/Source/bindings/core/v8/NPV8Object.cpp
+++ b/Source/bindings/core/v8/NPV8Object.cpp
@@ -561,8 +561,8 @@ bool _NPN_Enumerate(NPP npp, NPObject* npObject, NPIdentifier** identifier, uint
         ASSERT(result->IsFunction());
         v8::Local<v8::Function> enumerator = v8::Local<v8::Function>::Cast(result);
         v8::Local<v8::Value> argv[] = { obj };
-        v8::Local<v8::Value> propsObj = V8ScriptRunner::callInternalFunction(enumerator, v8::Local<v8::Object>::Cast(result), WTF_ARRAY_LENGTH(argv), argv, isolate);
-        if (propsObj.IsEmpty())
+        v8::Local<v8::Value> propsObj;
+        if (!V8ScriptRunner::callInternalFunction(enumerator, v8::Local<v8::Object>::Cast(result), WTF_ARRAY_LENGTH(argv), argv, isolate).ToLocal(&propsObj))
             return false;
 
         // Convert the results into an array of NPIdentifiers.