With the introduction of ch11ng/xelb@6a7bccc, many weird behaviors should
disappear. These include by not limit to
* race conditions when managing a window (a workaround is provided in @14628a9)
* race conditions when unmanaging a window
This commit removes some corresponding code.
* Make sure `exwm-manage--manage-window-queue` is cleaned
* Improve input focus handling after unmanaging a window
* Remove a redundant call to `exwm-layout--show`
Since it takes some time for EXWM to create a buffer for a window (to do some
checking for example), the window may send several MapRequest events before
it's mapped. This commit should fix such issue.
* Correct ConfigureNotify events sent to fullscreen windows.
* Exit fullscreen mode before switching workspace.
* Temporarily treat `xcb:Atom:_NET_WM_STATE_ABOVE` as
`xcb:Atom:_NET_WM_STATE_FULLSCREEN` since
a) "plugin-container" (Flash Player) seems only set this, and
b) it's not normally used by applications.
This makes fullscreen videos working in e.g. iceweasel.
