Reuse SIRT for C++ references

Change-Id: I8310e55da42f55f7ec60f6b17face436c77a979f
diff --git a/src/exception_test.cc b/src/exception_test.cc
index 29d91bb..ab462a9 100644
--- a/src/exception_test.cc
+++ b/src/exception_test.cc
@@ -19,8 +19,8 @@
   virtual void SetUp() {
     CommonTest::SetUp();
 
-    const ClassLoader* class_loader = LoadDex("ExceptionHandle");
-    my_klass_ = class_linker_->FindClass("LExceptionHandle;", class_loader);
+    SirtRef<ClassLoader> class_loader(LoadDex("ExceptionHandle"));
+    my_klass_ = class_linker_->FindClass("LExceptionHandle;", class_loader.get());
     ASSERT_TRUE(my_klass_ != NULL);
 
     dex_ = &Runtime::Current()->GetClassLinker()->FindDexFile(my_klass_->GetDexCache());