RFR 8235678: Remove unnecessary calls to Thread::current() in MutexLocker calls

[Harold Seigel]

Hi,

Please review this small change, to reduce unnecessary calls to 
Thread::current() in MutexLocker calls, by passing the current thread as 
an argument.  A few ResoureMark declarations were also changed.

Open Webrev: 
http://cr.openjdk.java.net/~hseigel/bug_8235678/webrev/index.html

JBS Bug: https://bugs.openjdk.java.net/browse/JDK-8235678

The fix was regression tested by running Mach5 tiers 1 and 2 tests and 
builds on Linux-x64, Solaris, Windows, and Mac OS X, by running Mach5 
tiers 3-5 tests on Linux-x64, and JCK lang and VM tests on Linux-x64.

Thanks, Harold