hg: nashorn/jdk8/nashorn: 8015892: canBeUndefined too conservative for some use before declaration cases

[marcus.lagergren at oracle.com]

Changeset: 8f890b6bf6de
Author:    lagergren
Date:      2013-06-10 13:21 +0200
URL:       http://hg.openjdk.java.net/nashorn/jdk8/nashorn/rev/8f890b6bf6de

8015892: canBeUndefined too conservative for some use before declaration cases
Reviewed-by: attila, hannesw

! src/jdk/nashorn/internal/codegen/Attr.java
! src/jdk/nashorn/internal/ir/Symbol.java
+ test/script/basic/JDK-8015892.js
+ test/script/basic/fib_wtf.js
+ test/script/basic/fib_wtf.js.EXPECTED