Move to dalvik.vm.lib.2 to force default to libart

Bug: 14298175

(cherry picked from commit 7e127ebe0bf8753fcbeeac6140916d512322e308)

Change-Id: I0a94e01f46fcc074d8c8fd1e5558fb764ab47361
diff --git a/CleanSpec.mk b/CleanSpec.mk
index c64f316..76653f4 100644
--- a/CleanSpec.mk
+++ b/CleanSpec.mk
@@ -227,6 +227,9 @@
 $(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/build.prop)
 $(call add-clean-step, rm -rf $(PRODUCT_OUT)/root/default.prop)
 
+# Rename persist.sys.dalvik.vm.lib.1 to allow new default
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/build.prop)
+
 # ************************************************
 # NEWER CLEAN STEPS MUST BE AT THE END OF THE LIST
 # ************************************************