Small KApplication cleanups

[Maksim Orlovich]

> Hi all
>
> While looking into kapplication.cpp, I have seen some things that are not
> really nice or not required anymore. Please see the attached patch.

<snip>

> If there are no objections, I will commit these small changes tomorrow.

Could you please consider waiting until after 4.0? I don't see how this
change can fix anything, it could just break things. At the very least,
please wait for feedback from Seli on the X bits you touched.

-Maks