[11u] RFR: 8213448 [TESTBUG] enhance jfr/jvm/TestDumpOnCrash

[Jie Kang]

Hi all,

Please review this test-only backport of 8213448 to OpenJDK jdk11u-dev
so as to get a significantly cleaner backport for JDK-8217362 [1]. The
fix did not apply cleanly as a one-line removal to the file is missing
from JDK-8209856 [2]. My process was to make this one-line removal,
apply the patch, and then revert the one line removal. I have run tier
one tests and jfr specific tests successfully. Please let me know how
it looks and if it is appropriate to backport to 11.

Webrev: http://cr.openjdk.java.net/~jkang/jdk-8213448/webrev.00/
Original Changeset: http://hg.openjdk.java.net/jdk/jdk/rev/f0af7fd0c9ca
Bug: https://bugs.openjdk.java.net/browse/JDK-8213448

[1]
Would allow a cleaner backport of:
http://hg.openjdk.java.net/jdk/jdk/rev/3cabb47758c9#l5.1
https://bugs.openjdk.java.net/browse/JDK-8217362

[2]
The missing one-line removal:
http://hg.openjdk.java.net/jdk/jdk/rev/d7fc38d3fc8d#l19.7
https://bugs.openjdk.java.net/browse/JDK-8209856