this seems to be a problem since....

commit 199eb08b
Author: Miklos Vajna <vmiklos@collabora.co.uk>
Date:   Thu Jun 5 16:25:01 2014 +0200

    SwAnchoredDrawObject::GetObjBoundRect: avoid SwDoc::SetModified()

    This is a const method, but it does a const_cast to still resize an
    object... if that's so, then we should ensure that the "is modified"
    flag of SwDoc is untouched.

    CppunitTest_sw_ooxmlimport's testChartSize is a reproducer for this,
    when shape text is imported as textbox.

(note under gtk3 and wayland this isn't as noticable, there use
export GDK_BACKEND=x11 to reproduce the freeze effect where even
the mouse cursor doesn't move during part of the load)

Change-Id: Ic0bd98b032dfe1255d79d8070d50f65fcfa676dd
Reviewed-on: https://gerrit.libreoffice.org/31687Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>