Assume that every undo item is non-null => remove some "defensive" checks.
Assume that every undo item is non-null => remove some "defensive" checks.

svn path=/trunk/KDE/kdelibs/kate/; revision=960596

cmacq2/kate,sandsmark/kate,hlamer/kate,hlamer/kate,hlamer/kate,hlamer/kate,hlamer/kate,hlamer/kate,sandsmark/kate,jfmcarreira/kate,sandsmark/kate,DickJ/kate,jfmcarreira/kate,hlamer/kate,DickJ/kate,DickJ/kate,DickJ/kate,jfmcarreira/kate,hlamer/kate,hlamer/kate,cmacq2/kate,cmacq2/kate,sandsmark/kate,hlamer/kate