This prevents issues from happening when processing Enter/Leave events
while in another kind of grab op like a Wayland popup or resizing a
window.
This can't ever really happen except outside of a race condition,
with the X server, since we won't ever pass input events to the
X server in any of these cases, but it can't hurt to be more correct
about what the intended operation is.
GTK+ focuses its own windows with RevertToParent, which means that when
a GTK+ CSD window is destroyed, the X server will set the focus back to
the root window. The event stream that we is an UnmapNotify followed by
a FocusOut event. Our own UnmapNotify-handling code unmanages the window
and forcibly changes the focus to the next default window in the stack.
Since UnmapNotify events don't come with timestamps, we query for one,
and set the window focus using that.
But there's *still* a FocusOut event in the stack, with an older
timestamp and serial than our own focusing. We see this, throw it out
since it's older than the most recent focus, but then our own code that
notices the root has been focused kicks in and tries to focus the
default window... using a timestamp older than our most recent focusing.
meta_display_sanity_check_timestamps notices this, and (rightly so)
puts a warning in our face, telling something is awry.
Only let our workarounds kick in when the event is new enough, otherwise
our code will get confused over old events.
This stops the:
Window manager warning: last_focus_time (367917173) is greater than comparison timestamp (367917170). This most likely represents a buggy client sending inaccurate timestamps in messages such as _NET_ACTIVE_WINDOW. Trying to work around...
warning spam when closing a CSD window.
When the screen resizes, we get a configure event for the composite overlay
window - don't pass that to MetaStackTracker, since the COW isn't in the
stack.
Fixes warning:
mutter-WARNING **: STACK_OP_RAISE_ABOVE: window 0x65 not in stack
Add a private hook for the test framework to get XSyncAlarmEvent events -
this will be used to implement XSyncCounter based synchronization
so that the test framework can deterministically wait until Mutter
has seen actions performed by an X11 client.
https://bugzilla.gnome.org/show_bug.cgi?id=736505
This is so we won't poke into the MetaDisplay, which is invalid memory,
and crash. This can sometimes work right now because GSlice might not
deallocate the object immediately, but it's still not a fun thing to do.