RFR: 8274245: sun/tools/jmap/BasicJMapTest.java Mutex rank failures

[Coleen Phillimore]

This test fails due to Mutex rank assertions that I just added.  The new mutexes in the heapDumper needs to be ranked 'nosafepoint' and 'nosafepoint-1' since they don't cause safepoint checks.
This code also holds two no-safepoint checking locks and waits on the second.  This doesn't break rank ordering but does run afoul of an old assert that we had in the code, that is no longer has meaning.

The test still fails because of other bugs like JDK-8274196 but it doesn't get the mutex rank assertions anymore.

Testing with tier 5 and 6, where the failure was observed, in progress.

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Commit messages:
 - 8274245: sun/tools/jmap/BasicJMapTest.java Mutex rank failures

Changes: https://git.openjdk.java.net/jdk/pull/5669/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=5669&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8274245
  Stats: 9 lines in 3 files changed: 0 ins; 3 del; 6 mod
  Patch: https://git.openjdk.java.net/jdk/pull/5669.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/5669/head:pull/5669

PR: https://git.openjdk.java.net/jdk/pull/5669