This commit adds a resetTabColor(...) method to TQTabBar and TQTabWidget which allows the color of the appropriate tab to be reset to the default as specified by the desktop color scheme.
It also changes how invalid color values are handled; before, an invalid value would be used as a valid color, resulting in 0,0,0 (black). Seeing that an invalid color is returned by KColorDialog when the default color checkbox is checked, it makes more sense to ignore invalid colors, using the appropriate color from the color scheme instead.
Signed-off-by: Mavridis Philippe <mavridisf@gmail.com>
(cherry picked from commit c28a87c7d2)