public static Toggle fromDisplayValue(final String displayValue) {
            Objects.requireNonNull(displayValue);
            return "on".equalsIgnoreCase(displayValue)
                    ? ON
                    : OFF;
        }
Get the default editor theme that corresponds to the passed stroom theme name.
e.g. a dark editor theme for a dark stroom theme.
stroom-core-shared/src/main/java/stroom/ui/config/shared/UserPreferences.java