[8u] RFR: 8217362: Emergency dump does not work when disk=false is set

[Ekaterina Vergizova]

Hello,
I would like to backport JFR issue 8217362 to 8u.

JBS: https://bugs.openjdk.java.net/browse/JDK-8217362
Original patch: https://hg.openjdk.java.net/jdk/jdk/rev/3cabb47758c9
Webrev for 8u
  hotspot: https://cr.openjdk.java.net/~apetushkov/jfr_backports_katya/8217362/hotspot/webrev.00/
  jdk: https://cr.openjdk.java.net/~apetushkov/jfr_backports_katya/8217362/jdk/webrev.00/

The patch doesn't apply cleanly due to the context differences:
- different logging (tty->print_cr in 8u instead of log_info/log_error) and includes list in jfrRepository.cpp and jfrEmergencyDump.cpp
- different parameters of ProcessTools.createJavaProcessBuilder() in TestDumpOnCrash.java

I reapplied the changes manually:
- moved emergency dump methods from jfrRepository.cpp to jfrEmergencyDump.cpp
- incorporated the fix for emergency dump when disk=false and other small changes in emergency dump methods
- made sure the resulting patch differs from the original patch only by the context differences described above

Tested with tier1 and jdk.jfr tests on Linux and Windows.

Thanks,
Ekaterina