binidngs: Make callInternalFunction return MaybeLocal

Source/bindings/core/v8/V8PerIsolateData.cpp

Index: Source/bindings/core/v8/V8PerIsolateData.cpp
diff --git a/Source/bindings/core/v8/V8PerIsolateData.cpp b/Source/bindings/core/v8/V8PerIsolateData.cpp
index 40f100ab6f2f94e91580f052a881fece711fd004..3a5e09836cf42d8a4d613f43057820a46d40f19b 100644
--- a/Source/bindings/core/v8/V8PerIsolateData.cpp
+++ b/Source/bindings/core/v8/V8PerIsolateData.cpp
@@ -241,7 +241,10 @@ static void constructorOfToString(const v8::FunctionCallbackInfo<v8::Value>& inf
         v8SetReturnValue(info, v8::String::Empty(info.GetIsolate()));
         return;
     }
-    v8SetReturnValue(info, V8ScriptRunner::callInternalFunction(v8::Handle<v8::Function>::Cast(value), info.This(), 0, 0, info.GetIsolate()));
+    v8::Local<v8::Value> result;
+    if (!V8ScriptRunner::callInternalFunction(v8::Handle<v8::Function>::Cast(value), info.This(), 0, 0, info.GetIsolate()).ToLocal(&result))
+        result = v8::String::Empty(info.GetIsolate());
+    v8SetReturnValue(info, result);
 }
 
 v8::Handle<v8::FunctionTemplate> V8PerIsolateData::toStringTemplate()