JIT default opt-in

Bug: 17950037

(cherry picked from commit 2a2a03046ecea689ff8cc86b80c27c24905c2d60)

Change-Id: I97fd6b1797e54ad3dea1930889f32a717543490d
diff --git a/CleanSpec.mk b/CleanSpec.mk
index bfa236c..c0fe216 100644
--- a/CleanSpec.mk
+++ b/CleanSpec.mk
@@ -334,6 +334,11 @@
 $(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/app/*)
 $(call add-clean-step, rm -rf $(PRODUCT_OUT)/obj/APPS/*)
 
+# Adding dalvik.vm.usejit
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/system/build.prop)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/root/default.prop)
+$(call add-clean-step, rm -rf $(PRODUCT_OUT)/recovery/root/default.prop)
+
 # ************************************************
 # NEWER CLEAN STEPS MUST BE AT THE END OF THE LIST
 # ************************************************
diff --git a/core/main.mk b/core/main.mk
index 2c15d0f..a360d6c 100644
--- a/core/main.mk
+++ b/core/main.mk
@@ -393,6 +393,7 @@
   # Don't compile apps on eng builds to speed startup
   ADDITIONAL_BUILD_PROPERTIES += dalvik.vm.dex2oat-filter=interpret-only
 endif
+  ADDITIONAL_BUILD_PROPERTIES += dalvik.vm.usejit=true
 endif
 
 ## sdk ##