[rfc] [icedtea-web] Fix EDT hanging on OpenJDK 11

[Jiri Vanek]

> 
> I agree I simplified that code as I did not catch any reason why it is so complicated: I did not 
> figure out any real reason to catch 2 times (InterruptedException) in JNLPSplashScreen constructor + 
> setSplashImageURL() then loop on: while (!splashScreen.isSplashImageLoaded()) => it simply does not 
> make sense to me.
> 
> Any idea, Jiri ?
> 

Some.. And thats why I was not complaining abut it in review. It is old code, but AFAIR, the corner 
cases handled by that terrible construct, were actually caused by the issues in EDT we had.
So once the EDT is fixed, the simplified code should be perfectly ok.

J.