ui/console has a concept of "active" console; the active console is used
when NULL is set for DisplayListener::con, and console_select() updates
the active console state. However, the global nature of the state cause
odd behaviors, and replacing NULL with the active console also resulted
in extra code. Remove it to solve these problems.
The active console state is shared, so if there are two displays
referring to the active console, switching the console for one will also
affect the other. All displays that use the active console state,
namely cocoa, curses, and vnc, need to reset some of its state before
switching the console, and such a reset operation cannot be performed if
the console is switched by another display. This can result in stuck
keys, for example.
While the active console state is shared, displays other than cocoa,
curses, and vnc don't update the state. A chardev-vc inherits the
size of the active console, but it does not make sense for such a
display.
This series removes the shared "active" console state from ui/console.
curses, cocoa, and vnc will hold the reference to the console currently
shown with DisplayListener::con. This also eliminates the need to
replace NULL with the active console and save code.
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>