"Apply function signature change" does not work for std::function<void (...)>

When changing a template function and applying the signature change, the return type of the template is removed.

Steps to reproduce

1. Create a function in a class body and header: void MyClass::foo(const QString &val, std::function<void (QByteArray)> callback)
2. Change function body to: void MyClass::foo(const QString &val, std::function<void (const QByteArray &)> callback)
3. Apply function signature change.

What do you see

1. in header: void foo(const QString &val, std::function<(const QByteArray &)> callback)

What do you expect

1. in header: void foo(const QString &val, std::function<void (const QByteArray &)> callback)

The same happens if you change the signature in the header.
Adding the function is ok.