Fix the LDT code to be -O2 safe and valgrind clean.

Change-Id: Iad987f828a8d8932a9f7212c71eddd3c943f6311
diff --git a/build/Android.common.mk b/build/Android.common.mk
index 575c810..de2622a 100644
--- a/build/Android.common.mk
+++ b/build/Android.common.mk
@@ -25,7 +25,7 @@
 	dalvik/libdex
 
 ART_CFLAGS := \
-	-O0 \
+	-O2 \
 	-ggdb3 \
 	-Wall \
 	-Werror \