X.A.WindowNavigation: fix navigation being "stuck" in certain situations

[Rogach]

Description

Update left and right navigation to behave correctly even if the currently saved position is directly on the edge of the focused window. This makes the L/R behavior consistent with U/D navigation.

How to reproduce the issue:

• configure Grid layout;
• open 4 terminals;
• navigate to the top-right terminal;
• open another terminal;
• immediately close it;
• try navigating left from the currently focused top-right terminal;
• observe navigation being "stuck".

Minimized configuration to test the issue:

{-# OPTIONS_GHC -fno-warn-type-defaults #-}

import XMonad
import XMonad.Config.Xfce
import XMonad.Hooks.SetWMName
import XMonad.Layout.Grid
import XMonad.Actions.WindowNavigation

main :: IO ()
main = do
  myConfig <- withWindowNavigation (xK_k, xK_h, xK_j, xK_l) $
              xfceConfig
              { terminal = "gnome-terminal"
              , modMask = mod4Mask
              , layoutHook = GridRatio (4/3)
              , startupHook = do
                  startupHook xfceConfig
                  setWMName "LG3D"
              , workspaces = map show [0..15]
              }
  xmonad myConfig

Checklist

• [X] I've read CONTRIBUTING.md

• [x] I've considered how to best test these changes (property, unit, manually, ...) and concluded: I've tested the changes manually.

• [X] I updated the CHANGES.md file

[slotThe]

Minimized configuration to test the issue

I can't reproduce this with that config. What I did:

• M-S-<Enter> 4 times (open 4 terminals)
• M-l (navigate to the top-right terminal)
• M-S-<Enter> (open another terminal)
• M-S-c (immediately close it)

After that M-h correctly navigates left from the currently focused window (which is still in the upper right corner).

[Rogach]

What is your screen resolution? (mine is 2560x1440)

[Rogach]

Also, where is the 5th terminal opening for you? In my case it opens in bottom-center position, something like this:

x----x----x----x
|    |    |    |
|    x----x----x
|    | 5  |    |
x----x----x----x

[slotThe]

What is your screen resolution? (mine is 2560x1440)

I tried it through xephyr, so it was 800x600. Indeed, if I choose 1920x1080 or 2560x1440 I can reproduce the problem

[slotThe]

Your proposed fix seems to work; thanks! (I just pushed a small doc fix)