Currently, if a color scheme lacks the WM group, DecorationPalette
doesn't load it so we can fallback to kdeglobals color scheme. If
kdeglobals doesn't have WM group we get black decorations.
This change will always load the kdeglobals color scheme even if it
is missing WM group.
REVIEW: 123320
Adapt to API changes introduced by b62e8888cd39301e00ad98dfe791fa66676408fb.
It adds DecoratedClient::color(group, role) for getting colors that are
not included in QPalette. Breeze used to read these colors from
kdeglobals, breaking per window color schemes. KWin now handles reading
these colors along with QPalette loading with DecorationPalette.
REVIEW: 122883
