RFR: 8036701: Add trace event when a metaspace throws out of memory error

[Erik Helin]

Hi all,

this patch adds a new trace event for tracking metaspace out of memory 
exceptions - vm/gc/metaspace/out_of_memory. This patch builds upon the 
patch for "JDK-8036699: Add trace event when a metaspace allocation 
fails". The information in the allocation failure event and the OOM 
event are the same, see the review request for the allocation failure 
event for more information.

Webrev:
http://cr.openjdk.java.net/~ehelin/8036701/webrev.00/

Enhancement:
https://bugs.openjdk.java.net/browse/JDK-8036701

Testing:
- JFR JTREG tests
- JPRT

Thanks,
Erik