bug#11015: bug#9509: 23.3; [custom] "Reset to saved"

[Chong Yidong]

Dave Abrahams <dave@boostpro.com> writes:

> When I customize a setting, the customization buffer has a "reset to
> saved" button.  If any of the settings in that buffer have been
> changed and never saved, though, pressing that button generates
> an error:
>  
>   custom-variable-reset-saved: No saved value for <name-of-variable>.  
>
> It should instead simply revert those settings to their un-customized
> (default) state, while resetting everything else to its saved state.
> The saved state of those un-customized variables should be thought of as
> "not customized."

I've committed a patch to trunk that implements this.  Thanks.