[Qt] minor changes in splashscreen.cpp #4959

• guard an unused variable with Q_UNUSED() macro
• remove a commented out line of code

I disagree with this. The window has a minimize button. If you want to minimize, just hit minimize. Hitting close should be reserved for "emergency shutdown" (or "cancel startup") cases, but we don't support that at this point.

@laanwj Understood and changed to a minor uncontroversial pull.

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Thanks. utACK.

I've tried it and you can actually put a StartShutdown() in the CloseEvent of the splash screen and it appears to work. This is akin to doing Ctrl-C during initialization in bitcoind.

I also thought about adding a StartShutdown() to the close button, but that will perhaps also confuse users... not sure about that yet.

I think it's useful if you accidentally start the program to be able to stop it sooner. It's clear to the user what happens as the shutdown window appears. It's not potentially harmful either - the initialization is cancelled, but only in the next safe spot.