Use "conditional" skin element attribute to reduce log clutter for button hints

[prl]

The "conditional" attribute to skin elements can be used to remove skin warning messages if a skin element is specified for a widget, but there is no implementation of the widget.

This happens most often for the text widgets in coloured button hints where there's no corresponding (empty) implementation of the widget in the Screen.

To remove the warnings, a conditional attribute can be used on the widget implementation's key:

    <widget name="key_somecolour" conditional="key_somecolour" .../>
    <widget source="key_somecolour" conditional="key_somecolour" .../>

An example of the clutter can often be seen just by doing

grep key_ logfile

If none are seen seen, visit MENU>Setup>AV setup>Skin setup, and do the grep again.