RFR: 6913: Add daemon thread information to the console threads view [v2]

[Alex Macdonald]

On Sat, 10 Oct 2020 16:09:15 GMT, Jan S. <github.com+924885+jpstotz at openjdk.org> wrote:

>> I had an Java application which did not exit because of a non-daemon thread still running. Therefore I added a column
>> to the treads view that displays if a thread is a daemon thread or not.
>> oca: has been signed on 2019-01-17 (got positive response from Dalibor Topic on 2019-01-23).
>
> Jan S. has updated the pull request incrementally with one additional commit since the last revision:
> 
>   show error message for Java 8 VMs and older that do not provide isDaemon() in java.lang.management.ThreadInfo

@jpstotz Thank you for the revision, this is what I had in mind. I think the code looks good, and I verified that the
correct messages are showing on a jdk8 jvm vs. a jdk11 jvm.

One minor nit is that the message texts don't usually end in a period, so other than that needing being changed this
looks okay to me.

application/org.openjdk.jmc.console.ui/src/main/resources/org/openjdk/jmc/console/ui/messages/internal/messages.properties
line 178:

> 176: IS_DAEMON_NAME_TEXT=Daemon
> 177: IS_DAEMON_ERROR_VALUE=Data not available
> 178: IS_DAEMON_DESCRIPTION_TEXT=True if the thread is a daemon thread.

Minor nit, but I don't think there should be a period to end the statement

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PR: https://git.openjdk.java.net/jmc/pull/110