QmlJS: Fix crash.

Change-Id: Ieacc7896eaeb478c6bd79a0865280f0cb595101e
Reviewed-on: http://codereview.qt-project.org/5619

Reviewed-by: Fawzi Mohamed <fawzi.mohamed@nokia.com>

src/libs/qmljs/qmljsinterpreter.cpp

@@ -215,7 +215,7 @@ void QmlObjectValue::processMembers(MemberProcessor *processor) const
         if (_metaObjectRevision < method.revision())
             continue;
 
-        QString methodName;
+        const QString &methodName = _metaObject->method(index).methodName();
         const Value *signature = signatures->at(index);
 
         if (method.methodType() == FakeMetaMethod::Slot && method.access() == FakeMetaMethod::Public) {