When an application inhibited idle, a view pointer was stored and a
destroy listener was registered to the wlr inhibitor. As the wlr
inhibitor lives longer than the view, this lead to a dangling view
pointer between view unmap and inhibitor destroy.
Store a pointer to the wlr inhibitor instead of to the view, and look up
the view when needed, which may at any point be NULL. This also allows
for an inhibitor to remain functional if a surface is re-mapped.
This implements the following command to set/unset a user idle
inhibitor for a view:
`inhibit_idle focus|fullscreen|open|none|visible`
The modes are as follows:
- focus: inhibited when the view is focused by any seat
- fullscreen: inhibited when the view is fullscreen (or a descendant of
a fullscreen container) and is visible on any output
- open: inhibited until the view is closed or the inhibitor is unset or
changed
- none: unsets any user set idle inhibitors for the view
- visible: inhibited when the view is visible on any output
This should have no effect on idle inhibitors set by the applications
themselves and those should still work as intended.
Since this operates on the view in the handler context, it is possible
to set it on the currently focused view, on any existing view with
criteria, or for any future view with for_window.
