fs_rom closing and re-opening watches

[Pirmin Duss]

Hello Genodians

While debugging an error int the watch implementation of lx_fs, I
observed, that fs_rom often closes and re-opens the watch handles.

Whenever the file is read, the watch is closed and then re-opened. This
also happens, when the read was triggered by a watch notification from
the file system.

Is there a special reason for that? Or is this an oversight?

In https://github.com/genodelabs/genode/issues/3897 Norman already
stated, that fs_rom will probably undergo a rework to clean up some
design issues he has spotted. If this is an oversight, I think it would
be best to fix this when the rework is done.

Best regards,
Pirmin