RFR: 8195979: [Graal] crash in src/hotspot/share/runtime/mutex.cpp:1341 when Graal JIT is used

[Kim Barrett]

Please review this workaround for a lock rank ordering issue. When
using Graal, JNI references are released while holding the
Patching_lock (a rank=special lock).

Before the reimplementation of JNI global and weak global handles
using OopStorage (JDK-8194312), releasing such references was
accomplished without any locking. However, OopStorage::release
sometimes locks its allocation mutex. This change led to the reported
lock rank order problem for Graal.

As a temporary workaround we're reducing the ranks of the JNI
oopstorage mutexes, making them more special than "special", so they
can be locked while holding the Patching_lock. A better solution
(JDK-8196083) is being developed, but may take a little time. In the
interest of unblocking Graal testing, the simple rank reduction is
being proposed, even though it's ugly.

CR:
https://bugs.openjdk.java.net/browse/JDK-8195979

Webrev:
http://cr.openjdk.java.net/~kbarrett/8195979/open.00/

Testing:
Mach5 hs-tier{1-5}, jdk-tier{1-3}
Local testing of Ekaterina's reproducer in CR.