This also adds the ability to query how many virtual desktops are
set up, and for the Taskbar to be notified when the active virtual
desktop has changed.
This sets the stage so that DisplaySettings can configure the screen
layout and set various screen resolutions in one go. It also allows
for an easy "atomic" revert of the previous settings.
This allows WindowServer to use multiple framebuffer devices and
compose the desktop with any arbitrary layout. Currently, it is assumed
that it is configured contiguous and non-overlapping, but this should
eventually be enforced.
To make rendering efficient, each window now also tracks on which
screens it needs to be rendered. This way we don't have to iterate all
the windows for each screen but instead use the same rendering loop and
then only render to the screen (or screens) that the window actually
uses.
Make the taskbar 27 pixels tall instead of 28. This makes the button
icons and applets vertically centered.
On a related note, this required touching *way* too many places..
SPDX License Identifiers are a more compact / standardized
way of representing file license information.
See: https://spdx.dev/resources/use/#identifiers
This was done with the `ambr` search and replace tool.
ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt *
This leaves menu applets running but invisible, and that's a regression
we need to take care of obviously. But not today, because it's getting
too late.
