RFR 8072595: nashorn should not use obj.getClass() for null checks

[Hannes Wallnoefer]

+1

Am 2015-02-05 um 09:25 schrieb A. Sundararajan:
> Please review http://cr.openjdk.java.net/~sundar/8072595/ for 
> https://bugs.openjdk.java.net/browse/JDK-8072595
>
> See also: http://cr.openjdk.java.net/~shade/scratch/NullChecks.java
>
> PS. Piggybacking a script engine test (which fails in 8u31 but passes 
> in 8u40 - not sure if we had a test to cover it and hence adding it) 
> and couple of minor issues with sample code as well.
>
> Thanks,
> -Sundar