D29685: Grant keyboard focus to popups on popup

cblack created this revision.
cblack added a reviewer: KWin.
Herald added a project: KWin.
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REVISION SUMMARY
  This grants the keyboard focus to popups; fixing oddities with popups from the shell being unable to grab keyboard focus. This utilises the same approach as what Mutter does for popups in GNOME, resulting in expected behaviour: granting keyboard focus to a popup on its creation.

TEST PLAN
  Before: popups from panels cannot focus.
  After: popups from panels can focus.

REPOSITORY
  R108 KWin

BRANCH
  cblack/grant-keyboard-to-popups (branched from master)

REVISION DETAIL
  https://phabricator.kde.org/D29685

AFFECTED FILES
  keyboard_input.cpp
  xdgshellclient.cpp

To: cblack, #kwin
Cc: kwin, Orage, cacarry, LeGast00n, The-Feren-OS-Dev, cblack, jraleigh, zachus, fbampaloukas, mkulinski, ragreen, jackyalcine, iodelay, crozbo, bwowk, ZrenBot, ngraham, alexeymin, himcesjf, lesliezhai, ali-mohamed, hardening, romangg, jensreuterberg, abetts, sebas, apol, ahiemstra, mart