Add root types and thread id to root visiting.

Enables us to pass the root type and thread id to hprof.

Bug: 12680863
Change-Id: I6a0f1f9e3aa8f9b4033d695818ae7ca3460d67cb
diff --git a/runtime/mirror/class.cc b/runtime/mirror/class.cc
index 8051c9b..99a35e3 100644
--- a/runtime/mirror/class.cc
+++ b/runtime/mirror/class.cc
@@ -50,9 +50,10 @@
   java_lang_Class_ = NULL;
 }
 
-void Class::VisitRoots(RootVisitor* visitor, void* arg) {
+void Class::VisitRoots(RootCallback* callback, void* arg) {
   if (java_lang_Class_ != nullptr) {
-    java_lang_Class_ = down_cast<Class*>(visitor(java_lang_Class_, arg));
+    java_lang_Class_ = down_cast<Class*>(
+        callback(java_lang_Class_, arg, 0, kRootStickyClass));
   }
 }