METHOD_NOW_FINAL false positive on `private …` to `protected final …` change

[chrisvest]

I had the following method:

    private boolean useIpv6(InetAddress address) {
        …
    }

and changed it to

    protected final boolean useIpv6(InetAddress address) {
        …
    }

which produced the following complaint from japicmp:

There is at least one incompatibility: io.netty.channel.unix.Socket.useIpv6(java.net.InetAddress):METHOD_NOW_FINAL

I worked around it by introducing a static method in https://github.com/netty/netty/pull/11588/commits/2b7057562d3d5bf722e910289ad90dd733291ec1 but I think that should not be necessary.

This is with using japicmp maven plug-in version 0.15.3.

[normanmaurer]

This might be a duplicate of https://github.com/siom79/japicmp/issues/265