[Libreoffice] cppu::OPropertySetHelper ABI backwards compatibility

[Lionel Elie Mamane]

Hi,

I'm writing about your commits

11207ae93191fb966676423e6d377c8292a8cf0b
    Make XPropertSet2 not a child interface of XPropertySet.

    This is to preserve ABI backward compatibility with
    cppu::OPropertySetHelper.

80b1e662777100a7dfd80176a2b528880a838167

    Added XPropertySet2 to allow disabling of change event
    notifications.