I did not notice this before, as my user profile had a custom window
size; but with an empty user profile the buffer had a 0,0 size, so the
buffered result was empty, as no ImplHandleResize() was invoked.

Change-Id: Ie299ad1323944941afc407dc90f2459d72885d42
(cherry picked from commit 968bc55a)
Reviewed-on: https://gerrit.libreoffice.org/17532Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Tomaž Vajngerl <quikee@gmail.com>