Bug Fixes in Office
Fixes: kword freeze after click on print preview
Details: The printing framework assumes multi-threading, which allows the printing app to wait for the main thread to finish things like text layout.
After I changed the print-preview to be non-threaded due to the limitation of the print-priview-dialog I introduced the possibility for a deadlock.
Fixing this by only locking if we are called from the non-main thread.