Compaction cleanup for FindArrayClass.

We now pass double pointer in to signify that it can cause thread
suspension, this double pointer gets wrapped by a handle if don't
find the array class in the cache.

Change-Id: I43436b6c35597c7252b65d1180baddb5ac4caabb
diff --git a/runtime/class_linker.h b/runtime/class_linker.h
index a8271ed..ccf0558 100644
--- a/runtime/class_linker.h
+++ b/runtime/class_linker.h
@@ -84,7 +84,7 @@
       SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Finds the array class given for the element class.
-  mirror::Class* FindArrayClass(Thread* self, mirror::Class* element_class)
+  mirror::Class* FindArrayClass(Thread* self, mirror::Class** element_class)
       SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
   // Reutrns true if the class linker is initialized.