At the moment when a user edits a system-wide color scheme the changes are save in ~/.local/share/konsole; if the user wishes to reset the changes to that scheme and restore the original settings of the scheme in /usr/share/konsole he would have to "remove" the color scheme and restart konsole for the original color scheme to show in the ColorSchemeManager. Now there's a "Defaults" button in the ColorSchemeManager to reset a color scheme to the default values.
This fixes bug 369481 [1]