tdf#159213: fix Base crash when choosing "Help" in relations design (kf5)

There are 2 parts here:
1) in vcl/qt5:
- for release versions: avoid to call QtAccessibleRegistry::getQObject on a null object
- for debug version: add an assertion on object to check it's not null

2) in svtools:
the specific root cause  was in EditBrowseBox::DeactivateCell,
we must check m_aImpl->m_xActiveCell in addition to isAccessibleAlive()

Import remark: I had a very naive/bandaid patch at the beginning
this one is entirely thanks to Michael Weghorn

Change-Id: I90214e9c5b7c0aa45481915d7be6020a7dc8c42e
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/162182
Reviewed-by: Michael Weghorn <m.weghorn@posteo.de>
Tested-by: Jenkins
(cherry picked from commit 1a637a07a0fb23f4d4bfac69378caff7ee965737)
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/162141

0 files changed, 0 insertions, 0 deletions