RFR: sh/jdk11 assert failure because IfNode input is a Phi

[Roland Westrelin]

> I was trying to write a test case for that bug so I could fix it in
> jdk/jdk and then I realized that the fix above was addressing the
> consequence of logic that was missing and should have been
> backported. So I'd like to back it out and backport what's missing
> instead:
>
> http://cr.openjdk.java.net/~roland/shenandoah/LRBafterCallUseBool/webrev.01/

Anyone to approve this?

Roland.