Dereference the loop variable rather than the original list head. This
fixes a regression introduced in 4413b86a3 ("backends: Replace
ClutterDeviceManager usage in favor of ClutterSeat", 2019-10-04) which
broke button scrolling with trackballs.
x11: Forward current selection state when initializing X11 selections
Most visible with xwayland-on-demand, at the time of setting things up
for X11 selections, we don't forward the current state. This makes the
first started X11 app oblivious to eg. the current clipboard.
Syncing selections up at the time of initializing the X11 selection
stuff ensures that doesn't happen.
clutter/gesture-action: Cancel gesture when disabling the action
Like the click action, it makes sense to cancel the ongoing gesture
when the action is disabled. Do so by overriding our new friend,
ClutterActorMeta.set_enabled, and canceling the gesture when disabling
the action.
ClutterClickAction, like other actions, can potentially be disabled
at any time (that is not during painting). When that happens with
ClutterClickAction, it must release all timeouts and disconnect from
the stage's 'capture-event'.
Override ClutterActorMeta.set_enabled and release the click action
when the action is being disabled.
