Add validate object, clean up stack indirect reference table.

Change-Id: Ifb329ae7d3bede3e95d48e6761cee1412a33d867
diff --git a/src/indirect_reference_table.h b/src/indirect_reference_table.h
index 857b9cd..358162c 100644
--- a/src/indirect_reference_table.h
+++ b/src/indirect_reference_table.h
@@ -105,10 +105,10 @@
  * For convenience these match up with enum jobjectRefType from jni.h.
  */
 enum IndirectRefKind {
-    kInvalid    = 0,
-    kLocal      = 1,
-    kGlobal     = 2,
-    kWeakGlobal = 3
+    kSirtOrInvalid = 0,
+    kLocal         = 1,
+    kGlobal        = 2,
+    kWeakGlobal    = 3
 };
 std::ostream& operator<<(std::ostream& os, IndirectRefKind rhs);