so it doesn't get removed again from sal/inc/pch/precompiled_sal.hxx
(see commit 4af9612f).

Also make necessary changes to some of the files that start to fail
building after running bin/update_pch.sh, so that the patch is
self-contained and leaves the tree in fully functional state.

tools namespace had to be prepended with :: to disambiguate from
drawinglayer::tools

vcl/inc/window.h includes were amended, because ExtTextInputAttr is
from vcl/commandevent.hxx, and enum class ShowTrackFlags is from
vcl/window.hxx

Change-Id: I47179622350754cba2f95d26a1bafd3dfbbc935b
Reviewed-on: https://gerrit.libreoffice.org/42559Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Mike Kaganski <mike.kaganski@collabora.com>