Okay, I've spent a whole day on this now, and it finally kinda works!
With this patch, CObject and all of its derived classes are reference
counted instead of tree-owned.
The previous, Qt-like model was nice and familiar, but ultimately also
outdated and difficult to reason about.
CObject-derived types should now be stored in RefPtr/NonnullRefPtr and
each class can be constructed using the forwarding construct() helper:
auto widget = GWidget::construct(parent_widget);
Note that construct() simply forwards all arguments to an existing
constructor. It is inserted into each class by the C_OBJECT macro,
see CObject.h to understand how that works.
CObject::delete_later() disappears in this patch, as there is no longer
a single logical owner of a CObject.
Now that we can set icons directly "by bitmap", there's no need for passing
around the icon paths anymore, so get rid of all the IPC and API related
to that. :^)
Now that we support more than 2 clients per shared buffer, we can use them
for window icons. I didn't do that previously since it would have made the
Taskbar process unable to access the icons.
This opens up some nice possibilities for programmatically generated icons.
This behavior and API was extremely counter-intuitive since our default
behavior was for applications to never exit after you close all of their
windows.
Now that we exit the event loop by default when the very last GWindow is
deleted, we don't have to worry about this.
These events are identical, so it's silly to send both. Just broadcast
window state changes everywhere instead, it doesn't matter when it was
added as clients are learning about this asynchronously anyway.
I originally thought I would do this inside WindowServer, but let's try to
make it as a standalone app that communicates with WindowServer instead.
That will allow us to use LibGUI. :^)
