I noticed the oom_killer script wasn't working in our 5.2 deployment.
In the bin/solr script, the OnOutOfMemoryError option is being passed as an arg to the jar rather than to the JVM. I moved it ahead of -jar and verified it shows up in the JVM args in the UI.
Also, I'm not sure what the SOLR_PORT and SOLR_LOGS_DIR args are doing--they don't appear to be positional arguments to the jar.
Attaching a patch against 5.2.