Cannot reassign 'volume-quiet' keys shortcuts

[Jymbob]

Scenario: User wants to always change volume 'quietly'. User opens dconf-Editor or similar and finds the keyboard shortcuts.

Expected behaviour: user can assign new keyboard shortcut to 'volume-up-quiet' and 'volume-down-quiet'
Actual behaviour: keys are not assignable, but hard-coded to <Alt>XF86AudioRaiseVolume and<Alt>XF86AudioLowerVolume

An oft-requested feature is to "stop the pips" when using media keys to change the volume. AskUbuntu has several unresolved questions about this issue.

The current solution is to use <Alt>XF86AudioLowerVolume and <Alt>XF86AudioRaiseVolume, but these are hard-coded keybindings.

Proposal: Add two new settings_keys: volume-up-quiet and volume-down-quiet, initially assigned as above, but assignable by the user. It then becomes relatively easy to swap the assignment of volume-up/down and volume-up/down-quiet.

To my untrained eye, it looks like there would need to be a minor modification to plugins/media-keys/shortcuts-list.h (to add the reference to the settings_keys) and to /data/org.gnome.settings-daemon.plugins.media-keys.gschema.xml.in.in (to set defaults)

If I had any real history with C, I'd submit a patch, but I don't, so I'm worried I've missed something vital.