Use ScopedArenaVector instead of std::vector in SSA transformation.

Change-Id: Ibf8471274f2d5e11fcc185044745434c3c82ed74
diff --git a/compiler/dex/mir_optimization_test.cc b/compiler/dex/mir_optimization_test.cc
index 69c394f..29c353a 100644
--- a/compiler/dex/mir_optimization_test.cc
+++ b/compiler/dex/mir_optimization_test.cc
@@ -188,7 +188,9 @@
   }
 
   void PerformClassInitCheckElimination() {
+    cu_.mir_graph->SSATransformationStart();
     cu_.mir_graph->ComputeDFSOrders();
+    cu_.mir_graph->SSATransformationEnd();
     bool gate_result = cu_.mir_graph->EliminateClassInitChecksGate();
     ASSERT_TRUE(gate_result);
     RepeatingPreOrderDfsIterator iterator(cu_.mir_graph.get());