Issue #10328: Use triggerDump and request exclusive access for J9 system dumps

[kgibm]

For details, see Issue #10328.

Validated this fix shows the J9RAS_DUMP_DO_EXCLUSIVE_VM_ACCESS bit flag:

$ bin/server javadump play --include=system
[...]
Server play dump complete in /opt/ibm/wlp/output/play/core.20200108.175308.13395.0002.dmp.
$ jdmpview -core /opt/ibm/wlp/output/play/core.20200108.175308.13395.0002.dmp
[...]
> !findcallsite dmpagent.c:1713
[...]
 !j9x 0x00002AD018012C30,0x0000000000000078	dmpagent.c:1713
Call site count = 9
> !J9RASdumpAgent 0x00002AD018012C30
[...]
	0x60: UDATA requestMask = 0x000000000000000D (13)

[LibbyBot]

Code analysis and actions

DO NOT DELETE THIS COMMENT.

• 2 product code files were changed.
• Please describe in a separate comment how you tested your changes.

[kgibm]

fixes #10328

[kgibm]

#build

[LibbyBot]

Your personal build request is at https://wasrtc.hursley.ibm.com:9443/jazz/resource/itemOid/com.ibm.team.build.BuildResult/_aT7EYDI4EeqR2OPTKpEBmw

Target locations of links might be accessible only to IBM employees.

[andymc12]

LGTM

[LibbyBot]

Your Open Liberty build results are ready for viewing.

• Unit test results are at http://public.dhe.ibm.com/ibmdl/export/pub/software/openliberty/runtime/personal/_aT7EYDI4EeqR2OPTKpEBmw/junit/index.html.
• Gradle log and image zip are at http://public.dhe.ibm.com/ibmdl/export/pub/software/openliberty/runtime/personal/_aT7EYDI4EeqR2OPTKpEBmw.

[LibbyBot]

The build kgibm-10332-20200108-1812
https://wasrtc.hursley.ibm.com:9443/jazz/resource/itemOid/com.ibm.team.build.BuildResult/_aT7EYDI4EeqR2OPTKpEBmw
completed and has errors or failures.

For help analyzing your personal build, go to https://cognitive.hursley.ibm.com/buildAnalysis.html?uuid=_aT7EYDI4EeqR2OPTKpEBmw

[kgibm]

Reviewed 2 PB errors and they are unrelated.