Revert "Revert "Revert "Revert "Add intrinsic for Reference.get()""""

Fixed TargetReg issue causing build failure for x86.
This reverts commit 9e82bd3f0ce9e5f5777bea2f752ff3e251d32f9f.

Change-Id: I7e6a526954467aaf68deeed999880dfe9aa5f06e
diff --git a/runtime/mirror/object.cc b/runtime/mirror/object.cc
index 5f88d54..bc5cbcb 100644
--- a/runtime/mirror/object.cc
+++ b/runtime/mirror/object.cc
@@ -57,7 +57,7 @@
       ALWAYS_INLINE SHARED_LOCKS_REQUIRED(Locks::mutator_lock_) {
     // Copy java.lang.ref.Reference.referent which isn't visited in
     // Object::VisitReferences().
-    DCHECK(klass->IsReferenceClass());
+    DCHECK(klass->IsTypeOfReferenceClass());
     this->operator()(ref, mirror::Reference::ReferentOffset(), false);
   }