RFR 8007984: Null pointer dereference in jdk/linux-amd64/democlasses/demo/jvmti/heapTracker/src/java_crw_demo.c

[Jaroslav Bachorik]

Please, review this simple fix in the demo code.

Issue : https://bugs.openjdk.java.net/browse/JDK-8007984
Webrev: http://cr.openjdk.java.net/~jbachorik/8007984/webrev.00
In an unlikely case of providing fatal_error_handler that does not 
terminate the application when a fatal error is reported. The patch 
calls abort() regardless of whether the fatal_error_handler was invoked 
or not.

Thanks,

-JB-