[mythtv] Recording group persistence

[Jim Stichnoth]

I have a few shortcuts in mainmenu.xml that end like this:
    <action>TV_WATCH_RECORDING Movies</action>

I also have a "TV Recording Playback" jump point defined, which is
equivalent to the TV_WATCH_RECORDING action without an argument.

I have noticed that when this action takes an argument (e.g. Movies),
the recording group filter is only temporary, in the sense that
DisplayRecGroup is not updated in the settings table.  This means that
the TV Recording Playback jump point starts with a seemingly random
group filter.

Is this a design decision, or an oversight?  I modified
PlaybackBox::setInitialRecGroup(initialGroup) to call
setGroupFilter(initialGroup) and it seems to do what I want.  There
may be things I'm missing because e.g. I don't use group passwords.

Jim