RFR: 8233343: Deprecate -XX:+CriticalJNINatives flag which implements Java…

[Coleen Phillimore]

This change deprecates the -XX:+CriticalJNINatives flag and removes the develop flag -XX:+StressCriticalJNINatives.
See CSR for more details.

This change also removes the lazy GC lock in the critical native transition, and runs the critical native function as
thread_in_Java.  I add a safepoint check at the end of the native function and transition to native and poll again for
the safepoint after the function if a safepoint is requested.

Tested with tier 1-6 (we have a few tests that use this).  And built on
linux-x86-open,linux-s390x-open,linux-arm32-debug,linux-ppc64le-debug.

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Commit messages:
 - 8233343: Deprecate -XX:+CriticalJNINatives flag which implements JavaCritical native functions

Changes: https://git.openjdk.java.net/jdk/pull/764/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=764&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8233343
  Stats: 1054 lines in 18 files changed: 106 ins; 898 del; 50 mod
  Patch: https://git.openjdk.java.net/jdk/pull/764.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/764/head:pull/764

PR: https://git.openjdk.java.net/jdk/pull/764