Revert "KDE4: sleep in yield for native file picker"

This reverts commit 380f3b4b6cbbe8e82b58ddf55e95c5005307b51f.

Conflicts:

	vcl/unx/kde4/KDEXLib.cxx
	vcl/unx/kde4/KDEXLib.hxx

(cherry picked from commit 52a2bde753fdf62cd8bb8498ef92abcce86e6c12)

Change-Id: I8528bd881dbe1aee228d61c06ae018f3a75449b1
Reviewed-on: https://gerrit.libreoffice.org/8704
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>