hg: valhalla/valhalla/jdk: Enhancement: improve MH access checks w.r.t. classes defined with Unsafe.dAC

[maurizio.cimadamore at oracle.com]

Changeset: c28ea949f8cc
Author:    mcimadamore
Date:      2015-06-15 19:00 +0100
URL:       http://hg.openjdk.java.net/valhalla/valhalla/jdk/rev/c28ea949f8cc

Enhancement: improve MH access checks w.r.t. classes defined with Unsafe.dAC
* Add new Unsafe.getHostClass() method (see related VM patch)
* Added recursive access check logic that walks through the hostclass chain

! src/java.base/share/classes/java/lang/invoke/MethodHandles.java
! src/java.base/share/classes/sun/invoke/util/VerifyAccess.java
! src/java.base/share/classes/sun/misc/Unsafe.java