We should use the Xkb API to query the direction of the key map,
depending on the group. To get a valid result we need to go over
the Unicode equivalents of the key symbols for each group, so we
should cache the result.
The code used to query and cache the key map direction is taken
from GDK.
https://bugzilla.gnome.org/show_bug.cgi?id=705779
As x11 considers num lock and scroll lock to be modifiers, code that
checks for an exact modifier combination will fail if naively done when
num lock or scroll lock are turned on. Applications that want to ignore
these modifiers will need to use XKB to manually mask out the modifier
state.
As it is very unlikely that applications will want to care about the
state of num lock or scroll lock for key press/key release events, mask
out the num lock and scroll lock keys automatically.
https://bugzilla.gnome.org/show_bug.cgi?id=690664
The x11 backend exposes a lot of symbols that are meant to only be used
when implementing a subclassed backend, like the glx and eglx ones.
The uninstalled headers are also filled with cruft declarations of
functions long since removed.
Let's try to clean up this mess.
If we have XKB support then we should be using it to turn on the
detectable auto-repeat; this allows avoiding the peeking trick
that emulates it inside the event handling code.
