RFR: 8254842: [JVMCI] copy thread name when attaching libgraal thread to HotSpot [v2]

[Doug Simon]

> This PR modifies `HotSpotJVMCIRuntime.attachCurrentThread` when it is called from within libgraal so that the name of
> the thread in the libgraal heap is used as the name of the peer thread created in HotSpot.
> This useful when viewing output such as `-XX:JVMCITraceLevel=1`. For example, here's sample output without this PR:
> JVMCITrace-1[Thread-0]: initializing JVMCI runtime -1
> JVMCITrace-1[Thread-0]: initialized JVMCI runtime -1
> and then with:
> JVMCITrace-1[LibGraalHotSpotGraalManagementInitialization]: initializing JVMCI runtime -1
> JVMCITrace-1[LibGraalHotSpotGraalManagementInitialization]: initialized JVMCI runtime -1

Doug Simon has updated the pull request incrementally with one additional commit since the last revision:

  add guarantee to clarify name argument must not be null

-------------

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/684/files
  - new: https://git.openjdk.java.net/jdk/pull/684/files/eb531fad..726faca5

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=684&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=684&range=00-01

  Stats: 2 lines in 1 file changed: 2 ins; 0 del; 0 mod
  Patch: https://git.openjdk.java.net/jdk/pull/684.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/684/head:pull/684

PR: https://git.openjdk.java.net/jdk/pull/684