Review Request: 8006513: Null pointer in DefaultMethods::generate_default_methods when merging annotations

[Stefan Karlsson]

http://cr.openjdk.java.net/~stefank/8006513/webrev.00/

This fixes a bug introduced in the fix for JDK-8005994. Which is 
surfacing now that HotSpot is combined with JDK8-b73. The failing code 
path was not exercised when JPRT and nightly testing ran with with JDK8-b72.

This fix is urgent and is going to be pushed soon, since it block all 
other pushes to hotspot-gc.

thanks,
StefanK